slice the zucchini
thin & layer some over
the casserole top

source, 6 servings
1 lb spinach, 1 sliced zucchini, olive oil, s&p, 1 t rosemary, 1 t thyme, 2 smashed cloves garlic, 3 eggs, 1/2 c milk, 3/4 c shredded gruyere, 1/4 c shredded parm
brown garlic, 1/2 zucchini, herbs & spices in oil; add spinach, wilt; add eggs, milk, gruyere; pour into oiled baking dish, top with parm & rest of zucchini; 375 F, 20 minutes; broil