Preheat oven to 350° F and spray a 9”x13” pan with nonstick cooking spray, set aside.
In a large bowl whisk together all the dry ingredients (flour, sugar, cocoa powder, baking soda and salt) until combined.
Add in the remaining wet ingredients (oil, milk, vanilla or peppermint extract and eggs) and mix with an electric hand mixer (or a stand mixer) beat until everything is blended and smooth.
Pour into the prepared baking pan and bake in the oven for 35-40 minutes, or until a toothpick inserted in the center comes out clean. Let cool completely.
To make the frosting:
Add the softened butter to a medium sized bowl and with an electric hand mixer, beat until smooth.
Stir in powdered sugar (one cup at a time) until blended.
Beat in the vanilla (or peppermint) extract and 1 tablespoon of the heavy cream at a time until it reaches the desired consistency.
Spread on top of cooled cake and sprinkle with crushed peppermint candy (if desired.)
Store in the refrigerator.
Notes
Check to make sure your baking soda is fresh. Usually if baking soda has been opened and is over 6 weeks old - it's time to get new baking soda.
In cake recipes, I like to use whole milk or 2% fat milk. If you use skim milk or milk substitutes, I can't guarantee that the texture and moistness will come out correct.
Depending on how much peppermint flavor you enjoy, you can use peppermint extract in the cake and the frosting. Or just use vanilla extract in the cake.
Store any uneaten cake in the refrigerator for up to 3 days. Make sure dish is covered.
This cake can be frozen for up to 3 months. Just make sure to store in an airtight container.