Cook the broccoli, saving 1/2 cup of the cooking water. Leave the cooked broccoli in the pan with the water and while still hot put in the cheese whiz and mix until melted. Set aside
In a small frying pan, melt 4 tablespoons of the butter, add the 2 tablespoons of the flour and the 1/4 cup of chopped onions and cook until the onions are soft
Whisk the eggs, add to pan with broccoli, and when the onion mixture is done add to the pan as well.
Pour all ingredients in a 1 1/2 quart buttered baking dish, top with crushed crackers, and drizzle the last 4 tablespoons of melted butter on the top. Cook in a 350 degree oven for 30-40 minutes until the top in browned .