Step 1: Turn on your slow cooker on high to perheat it.
Step 2: Put Top 'n' Fill, sugar, vanilla, hot water and honey in large mixing bowl. Beat until all blended.
Step 3: Add 3 eggs one at a time beating well after each addition. Sift in flour with wooden spoon than beat until well combined.
Step 4: Line slow cooker bowl with baking paper. Pour Batter into bowl. Cook 2 hours on high
Step 5: Melt the butter in pan on top of stove. Stir in tablespoons milk and brown sugar. For one minute boil vigorously.
Step 6: Turn stove off. Place saucepan on heat mat on bench and beat in 1/2 cup icing sugar. Allow to cool slightly, than add vanilla and remaining 1/2 cup icing sugar. If icing is too thick is add a little more milk.
Step 7: spread icing over cooled cake