Three generations have insisted on this dish at all family gatherings. It's over-the-top delicious and well worth the effort it takes to make it. No Thanksgiving meal is complete without a big helping of Party Green Beans.
Cook green beans with 2 T bacon drippings for 15-20 minutes. In a skillet, melt butter and add finely chopped onions, being careful not to burn. Cook on medium-low heat until onions are tender. Add flour and sour cream. Mix well. Add salt, pepper and sugar. Mix and add drained green beans.
Place in glass 13x9x2" casserole dish. Mix the Swiss and cheddar cheeses together and sprinkle on top of green bean mixture. Then sprinkle crushed corn flakes on top of cheese. (Crumble corn flakes as you sprinkle them over green beans) Drizzle melted butter over corn flakes
Bake at 350 for 20-30 minutes. May take longer if dish has been refrigerated before baking. Beans are ready when they are thoroughly heated and bubbly and cheese is melted.