Have you ever had Caramel Cake with Caramel Icing? It's a classic Southern treat! But instead of a layer cake, I made this into a thin sheet cake. Less time baking, more time eating, I say! It's really easy to put together.
Preheat your oven to 350 degrees F. Line an 18x13 inch half sheet pan* with parchment paper, or just spray it well with nonstick spray (or grease with butter).
In a medium saucepan, melt 1 cup butter and 1 cup water over medium high heat. Add 2 cups brown sugar and stir occasionally until it comes to a rolling boil (that means bubbles all the way across the top, not just the edges.) Remove from heat once it has come to a full boil.
Let it cool for a couple minutes, then add 2 teaspoons vanilla.
Add 2 cups flour to the pot, but don't mix yet. Add the salt and baking soda on top of the flour and use a small spoon to stir it into the flour (You don't want to accidentally get a chunk of salt or soda in your cake, ew).
Use a whisk to stir the flour mixture in. Try to get all the lumps out.
In a small bowl, whisk together the eggs and sour cream. Add this to the cake batter and stir until incorporated.
Pour the cake batter into the prepared pan and spread to the edges.
Bake at 350 for about 17-20 minutes, until a toothpick inserted in the center comes out with no batter on it. The edges of the cake will start to pull away from the side of the pan.
Let the cake cool for about 20 minutes before frosting.
Make the caramel icing: In a clean saucepan, melt 3/4 cup butter, 3 and 1/2 cups brown sugar, 1/2 cup + 1/3 cup evaporated milk (or heavy cream), and 1/4 teaspoon salt. Bring it to a boil over medium heat. Once it is at a rolling boil, stir constantly, watching for the consistency to thicken - it should coat the back of a spoon. As soon as it does, remove from heat (this may take as little as 3 minutes and as many as 10). Add 1 and 1/2 teaspoons vanilla and stir.
Fill a large bowl with ice water. Place the entire pan of frosting into the ice bath, making sure you don't get any water in the caramel. Stir constantly for 3-5 minutes, making sure to be scraping the edges of the pan. See photos. Keep an eye on it to make sure it doesn't harden up without you noticing! (Don't walk away. You can read in the comments about a bunch of people who waited too long and their caramel got too hard. Sometimes it takes 3 minutes, sometimes more.)
While it is still pour-able, pour the icing over the slightly cooled cake and spread to the edges.
Let the icing set for a few minutes before serving warm. This is really good with vanilla ice cream! It's so rich, you can cut it into pretty small pieces. (I mean. I don't. But I have a major sweet tooth.)
Notes
*I like this cake best in an 18x13 inch pan (makes for a thinner cake) but here are the times for other size pans:If you are baking this in a 9x13 inch cake pan, bake for 23-25 minutes. If you do a 15x10 jelly roll pan, bake for about 20 minutes. If you bake it in an 18x13 half sheet pan, bake for about 17-20 minutes.All of these times are going to vary because everyone's oven is different.