Pour melted butter in a baking pan. Stir in pecans. Toast at 350° for 10 minutes. Set aside to cool. , In a bowl, cream butter and sugar until light and fluffy. Add 1 egg at a time, beating well after each addition. Combine flour, baking powder and salt; add to creamed mixture alternately with milk. Stir in vanilla and 1 cup toasted pecans. Pour batter into 2 greased and floured 8-in. round baking pans. Bake at 350° for 30-35 minutes or until a toothpick inserted in the center comes out clean. Cool in pans 10 minutes before removing to wire racks to cool completely. , Meanwhile, for frosting, cream butter and sugar. Add milk and vanilla, beating until light and fluffy. Add additional milk if needed. Stir in remaining toasted pecans. Spread between the layers and over the top and sides of the cake.