Preheat oven to 350 degrees Fahrenheit, and grease a 9x13 pan. Cream together butter, oil, and sugars until smooth and creamy. Add egg, water, vanilla and almond extract and beat until smooth
Stir in flour, salt, baking powder until it is just combined—don’t over mix it. It doesn’t take much to combine it.
Spread dough in the greased pan and bake for 12-14 minutes. If they look underdone, don’t worry! They will continue to cook a little and set up in the pan as they cool. If baked for longer they’ll be dry and crumbly.
While the bars are baking, cream together butter and powdered sugar for frosting. Add milk 1 tablespoon at a time until frosting reaches the right consistency. Then add in the remaining frosting ingredients together until smooth. I like to frost the bars while they are just barely warm; it gives them a very smooth top. Feel free to top with sprinkles!
Cool completely before slicing and serving. I love mine chilled!