In a large pot, combine oats, milk, brown sugar, peanut butter, and eggs.

Mix well; bring to a boil.

As soon as the mixture boils, reduce heat to simmer. Simmer over medium heat, stirring regularly, 20 minutes or until thickened.

Once mixture is thick, stir in raisins.

Pour into greased 9x13 inch pan and top with chocolate chips.

Bake at 350 degrees for 30 minutes or until oatmeal is set.

Let stand 5 minutes.

Serve warm; top with milk or additional brown sugar if desired.