1/2 stick butter
2 tbsp. flour (or as needed)
Milk as needed for thickening
1 can cream of chicken soup
1 can tuna
1 can biscuits

In skillet melt butter, add flour. Stir in milk. Mix in can of soup and tuna. Pour into casserole dish, top with can of biscuits. Place in oven and bake at 350 degrees until biscuits are brown.