2 Tbs butter
1 Tbs all-purpose flour
1 Tbs cornstarch
2 tsp dry mustard
1 tsp seasoning salt
3/4 cup milk
2 cups chopped cooked broccoli
1 cup cooked brown rice
1 1/2 cups shredded cheddar or Swiss cheese
4 lg eggs, separated

Preheat oven to 325°F. Grease a 2-quart casserole dish.
Melt butter in medium saucepan over medium-high heat; add flour, cornstarch, dry mustard and seasoning salt.. Gradually whisk in milk; stirring until thickened and smooth. Stir in broccoli, cook to heat through, stirring occasionally.
Remove from heat; stir in cheese and cooked rice.
In clean bowl, beat egg whites until stiff peaks form. Set aside.
In separate bowl, beat yolks a bit just until blended; stir into rice mixture. Carefully fold in the beaten egg whites. Spoon mixture into prepared casserole dish.
Bake in preheated oven for 40-45 minutes until golden brown and firm to the touch. Serve immediately.