Crust:
2 cups brown sugarFudge filling:
1 (12 oz) package chocolate chipsTo make crust: Cream together butter and sugar. Mix in eggs and vanilla. Stir in dry ingredients and mix well. Set aside and make fudge filling.
To make fudge filling: In saucepan, mix together chocolate chips, milk, butter, and salt. Cook over medium heat and stir until smooth. Remove from heat and add vanilla and nuts.
To assemble bars: Spread 2/3 oatmeal mixture in 15.5-inch by 10.5-inch greased pan. Cover with filling. Dot with remainder of oatmeal mixture. Bake at 350 degrees for 25 to 30 minutes.