For the cake:
1/3 c. packed light brown sugar
1 1/4 c. granulated sugar
1 3/4 c. all-purpose flour
1/2 c. unsweetened cocoa powder
1 1/2 tsp. baking powder
1 1/2 tsp. baking soda
1 tsp. salt
1 c. milk plus 1 Tbsp. vinegar (add vinegar to milk)
1 c. boiling coffee
1/2 c. vegetable oil
1 tsp. vanilla extract
For the topping:
2 graham crackers
1 c. mini marshmallows
1 c. semi-sweet chocolate chips
Combine the dry ingredients then add the wet in a large mixing bowl. Scrape down the sides. The batter should be runny.
Butter the bottom and sides of the slow cooker then place down parchment paper to line the bottom.
Pour in the batter and place on lid. Bake cake on High for 30 minutes then reduce to Low and bake for 1 1/2 hours.
Remove lid and add topping. Crush graham crackers and sprinkle over cake surface; sprinkle mini marshmallows and chocolate chips. Replace lid and let melt for 20 - 30 minutes.
This recipe courtesy of Courtney's Sweets.