This moist and rich chocolate sheetcake is a mayonnaise cake with just a couple of slight modifications. While it would be wonderful with any mint frosting, mint Swiss buttercream is a really wonderful pairing. This is a great cake for a picnic, a pot luck, or to serve for dessert on any day. Easy dessert recipe to make, and even easier to eat! Modified slightly from my friend Jill O'Connor's wonderful (affiliate) Cake, I Love You.
4-6drops peppermint oilor 1/2-1 teaspoon of peppermint extract depending on how strong a mint flavor you want
320milliliters1 1/3 cup boiling water, (1 1/3 cup)
Instructions
Position your oven rack in the center of the oven. Preheat to 350F. Spray a 9"x13" rectangular cake pan with pan spray. Set aside.
Sift together the flour, cocoa powder, baking powder, and salt. Set aside.
In the bowl of your stand mixer fitted with the paddle attachment, beat the sugar and eggs on medium high speed until they reach the ribbon stage, about 5 minutes.
Add the mayonnaise and mint oil or extract, and beat until smooth, scraping the bowl as necessary.
With the mixer on low speed, alternate adding the sifted dry ingredients in three additions with the boiling water in two additions. Begin and end with the dry ingredients. Scrape bowl as necessary.
Scrape the batter into the prepared pan and bake for 40-45 minutes or until the cake springs back when pressed in the center, the edges are just starting to shrink from the sides of the pan, and the internal temperature of the cake is between 195F and 200F.
Remove to a rack to cool completely.
Frost with your favorite frosting, but man is this good with mint Swiss buttercream!
Video
Notes
You can freeze this cake, either frosted or unfrosted, for up to 2 months. I think it is easier to freeze by the slice if you have the room in your freezer. That way, you can take out the pieces you need to thaw them. Thaw either in the fridge (for the whole cake) or on the counter (for individual slices).