Hot Fudge Pudding Cake in a Crock Pot

1 ¾ c. packed brown sugar
¼ c. + 3 tsp. Cocoa
1 c. flour
2 tsp. Baking powder
¼ tsp. Salt
½ c. milk
2 tbsp. Melted butter
½ tsp. Vanilla
1 ¾ c. hot water
Mix 1 c. brown suger, 3 tsp. Cocoa, flour, baking powder and salt together. Whisk in milk, melted butter and vanilla. Spread evenly over a greased bottom of slow cooker. Mix remaining ¾ brown sugar and ¼ c. cocoa . Sprinkle evenly over the top of batter. Pour in hot water but DO NOT STIR. Cover and slow cook until a toothpick inserted 1 inch comes out clean. Cook on high two hours. Do not cook on low. Serve warm with ice cream or whipped topping.