Chewy Choc-oat-chip Bar Cookies

This recipe comes from the Quaker Oatmeal canister. I made it this morning for a get-together at the park.

1 c. butter or margarine
1 1/4 c. brown sugar
1/2 c. white sugar
2 eggs
2 Tbsp. milk
2 tsp. vanilla
1 3/4 c. flour
1 tsp. baking soda
1/2 tsp salt
2 1/2 c. oats
12 oz semi-sweet chocolate chips
1 c. nuts, chopped (optional)

Preheat oven to 375 F. Beat together margarine, and sugars until creamy. Add eggs, milk and vanilla; beat well. Add combined flour, baking soda and salt. Stir in oats, chocolate chips and nuts. Mix well. Press dough into ungreased 13 x 9 in baking pan. Bake 30 to 35 minutes.