1/2 c. butter
12 oz. semi-sweet chocolate chips
2 c. sugar
1 1/4 c. all purpose flour
2 tsp. vanilla
1/2 tsp. baking powder
1/2 tsp. salt
3 lg. eggs
1/2 c. chopped pecans

In a large microwave safe bowl, melt butter and chocolate chips on high for 90 seconds, stirring every 30 seconds. Stir in remaining ingredients except pecans and beat until smooth. Stir in pecans. Spread in a buttered 13 x 9 inch baking pan. Set aside.

MOUSSE TOPPING:

3/4 c. whipping cream
6 oz. pkg. semi-sweet chocolate chips
3 lg. eggs
1 1/2 tsp. vanilla
1/2 c. sugar
1/4 tsp. salt
1 c. chopped pecans

In a microwave safe bowl, melt chocolate chips with cream on high for 90 seconds, stirring every 30 seconds; cool slightly. In a mixer bowl, beat remaining ingredients, except pecans, until foamy. Stir in chocolate mixture. Pour mousse topping over brownie; sprinkle with pecans. Bake in a 350 degree oven for 50-55 minutes. Let cool 2 hours before cutting into squares.