Kahlua Pralines and Cream Brownies with Kahlua Butter Cream Frosting

Makes 16 brownies

Praline Crust (recipe follows)
2 (1 ounce) squares unsweetened chocolate
1/2 cup butter
2 large eggs
1/2 cup granulated sugar
1/2 cup packed brown sugar
2 teaspoons vanilla extract
1/4 cup Kahl