Method Melt butter, blend in flour and cook for a few minutes stirring constantly. Gradually add milk and continue stirring until sauce boils and thickens, add seasonings and shredded cheese and stir until cheese melts. Add pineapple, green capsicum, mushrooms and onion and mix well. Combine spaghetti with ¼ cup of parmesan cheese. In a casserole dish, layer half the spaghetti mixture and half the cheese sauce. Repeat layering once. Bake at 180°C for 20 minutes. Remove from oven and top with ham strips and remaining parmesan cheese. Return to oven for 10 minutes.