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St. Patrick's Day Cake

Happy St. Patrick's Day!

I’ve always loved St. Patrick’s Day. I remember building leprechaun traps in school and hoping I would actually see a leprechaun. My mom even kept the trap I made for a while, right where I could see it.

My husband served a mission in Ireland, so he has some fun traditional recipes we make for the holiday. We’re going to make The Donovan’s Irish Pasties for dinner, as well as custard to go on top of…well, anything sweet we have.

So, remember how I set a goal to make a cake for every month? So far I’m on track! This cake was really fun to make because I got to test out some complicated techniques that I’ve never tried before. They weren’t very hard to do, but it would definitely take some practice to perfect these techniques.

We’ll start out with the cake itself. It was simple, and I used the same cake recipe I used for the Valentine’s cake. (Please note that I did 1 1/2 recipe.) It’s such an amazing recipe! I did do some things wrong this time, which I’ll include in the notes of the recipe. The frosting was Cream Cheese Cookie Dough Frosting from Taste and Tell that was absolutely delicious! I did add a little too much peppermint extract though, so I wouldn’t use more than 1 tsp of extract if you decide to make this recipe.

The first experiment for this cake was marshmallow fondant, which I have never tried before in my life! (Really good tips here.) It was really easy to make, but it can tear easily. All in all, it looked good and was fun to try, but I don’t know if I’ll ever use fondant again. I feel like I could make it look better just using buttercream, and we ended up peeling it off before we ate it anyway because it tastes a little like plastic. So looking okay and tasting okay vs. looking nicer and tasting nicer….I’d take frosting over fondant. I’ve got nothing against professionals using it, but since I won’t be making many cakes…yet…frosting seems like the better option for me.

Next was the rainbow on top of the cake. Do you like it? It’s homemade sugar glass. I made a half-rainbow form out of foil, poured the liquid mixture into it, and spread it with food coloring. The hardest part was waiting for the liquid to reach the right temperature. It takes a while.

My last, but favorite, experiment was the potato candy. It’s butter, sugar, and coconut rolled in cinnamon. I can’t recall ever having coconut and cinnamon together, but it is AMAZING! And they are super easy to make too.

And as you can tell, my son loves frosting... :)

(Here is a printable version of the list below)

What You'll Need:

Cake

(More than original recipe)

  • 3 cups all-purpose flour

  • 3 cups granulated sugar

  • 1 ½ cup cocoa powder, unsweetened

  • 6 ounces semisweet chocolate or dark chocolate

  • 2 ¼ tsp baking soda

  • 2 ¼ tsp baking powder

  • 1 ½ tsp salt

  • 3 cups sour cream

  • 3/4 cup vegetable oil

  • 3 large eggs

Frosting

(More than original recipe)

  • 8 oz cream cheese, at room temperature

  • 10 oz unsalted butter, at room temperature

  • 1 1/3 cup brown sugar

  • 4-6 tablespoons milk

  • 2 teaspoon vanilla extract

  • ½-1 teaspoon mint extract (depending on how strong you want it)

  • 1 cup flour

  • 6 cups powdered sugar

  • green food coloring

  • 1 1/3 cup mini chocolate chips

Marshmallow Fondant

  • 4 cups marshmallows

  • 4 cups powdered sugar

  • 2 tablespoons water

  • black food coloring

Rainbow Sugar Glass

  • 1 3/4 cups sugar

  • 1 cup water

  • 1/2 cup light corn syrup

  • 1/8 teaspoon cream of tartar

  • red, blue, and yellow food coloring

Potato Candy

  • 2 tablespoons unsalted butter

  • 1 cup powdered sugar

  • 1/8 teaspoon vanilla extract

  • 2 teaspoons cinnamon, or more as needed

Decorations

  • chocolate gold coins

  • green glitter

Directions:

  1. Prepare the fondant one day to one week ahead.

  • Microwave the marshmallows in a large bowl for 1 minute. Stir until the marshmallows are as melted as they can get. Microwave them for 30 seconds more, if needed.

  • Add the black food coloring, until you get the color you want.

  • Add the powdered sugar.

  • Cover your hands with shortening and knead the fondant, adding water if it gets too dry.

  • Fold the fondant to where there is only one seam, rub it in shortening, then wrap in two layers of plastic wrap. Refrigerate. (Take out of the fridge about one hour before you want to decorate.)

  1. Make the sugar glass.

  • Make a form out of the foil in the shape of a half rainbow (or a full rainbow, if you want to try that). The diameter should be about 4 inches wide. Spray a sheet pan with cooking spray and set the foil on one end of the pan. The foil will only hold about 1/3 of the recipe, so you can pour the rest onto the greased sheet pan or make it into suckers…

  • Mix all the ingredients in a medium saucepan and dissolve over medium heat, stirring with a silicone spatula only until the sugar is dissolved. Once the mixture is clear, stop stirring.

  • Let it boil until it reaches 300 degrees F (about one hour). If you don’t have a thermometer, test it by dropping a small amount into cold water. If it makes an audible “crack” or hardens into hard threads in the water, it’s ready.

  • Pour about 1/3 of the mixture immediately into the foil and the rest onto the greased cookie sheet.

  • Quickly put a couple of drops of each food coloring (red, yellow, then blue) on top of the mixture and spread out with the spatula. It’s okay if the colors mix a little- that’s part of the rainbow.

  • Let it set for one hour, untouched. Once it’s hardened, it should be easy to remove from the foil.

  1. Follow directions for cake here. Make sure you use an extra-large bowl or make it in two batches. Use three 8-inch square pans. Refrigerate in pans for at least 30 minutes before cutting (otherwise it will crumble way too easily).

  2. Follow directions for frosting here. Do not refrigerate before frosting. If you do, you will need to take it out to thaw about two hours before frosting.

  3. Remove cakes from pans and level them. Stack the cake layers on top of each other with frosting between each layer.

  4. Cover, and refrigerate for at least 30 minutes.

  5. Trim the outer edge of the cake to desired shape. I did a rounded cube with sharp edges.

  6. Coat the entire outside of the cake with frosting, making it fairly smooth.

  7. Cover and refrigerate at least 30 minutes.

  8. Smooth the cake by covering it with a sheet of wax paper or parchment paper, and rubbing it firmly with your hand.

  9. Roll out the fondant into a circle. Spray or brush the cake with a tiny bit of water, just to make it moist. Carefully lift the fondant onto the cake and smooth it down on all sides. Cut off excess fondant and roll it into a ball.

  10. Roll out the excess fondant into one long piece, about 2 inches wide. Cut a long strip of fondant out with a pizza cutter, 1 inch wide and as long as you can make it. This will be the "mouth" of the bag. Attach this to the top of the cake, using water to "glue" it to the rest of the cake. Brush the rest of the fondant very, very lightly with water to make it shine. Let it firm up.

  11. Make the potato candy by mixing all the ingredients together except for the cinnamon. Divide into 4 balls. Roll each ball in the cinnamon. Refrigerate.

  12. Make a thin frosting out of ¼ cup each of shortening (or butter) and sugar, plus some green food coloring. Put into a Ziploc bag with a corner snipped off. Use this frosting to make decorations on the cake. (Leprechaun footprints, four-leaved clovers, lines, etc.) Sprinkle decorations with green glitter (optional).

  13. Place the rainbow on the cake, cutting a thin wedge out of the top if you need to, so the rainbow can stand up. (Note: The rainbow may start bending if it is not hard enough, so only place it on the cake right before serving).

  14. Surround the rainbow with gold coins and potato candy.

Well, that’s the cake for March! It’s not the best I’ve done, but it was fun and hopefully you enjoy it.

Do you have any ideas for April? Leave them in the comments below!

Want to read more? Check out these posts:

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