Zucchini Florentine
["3 (5-inch) zucchini, scrubbed and halved lengthwise", "2 Tbsp. minced onion", "3 Tbsp. butter", "2 pkg. frozen chopped spinach, thawed", "1/4 c. grated Parmesan cheese"]
["Prepare zucchini by scooping out pulp, leaving 1/4-inch shells; mince pulp.", "Melt butter in skillet and saute pulp and onion until tender.", "Squeeze water out of spinach.", "Add to zucchini mixture.", "Keep warm while making sauce."]
["zucchini", "onion", "butter", "Parmesan cheese"]