Can I make this casserole ahead of time?
Yes. Assemble the casserole (excluding half the fried onions on top) up to 24 hours ahead, cover, and refrigerate. Add the reserved onions just before baking. Bake from cold for 5–10 minutes longer.
Do I need to drain the canned green beans?
Yes. Drain the canned green beans thoroughly to prevent excess moisture in the casserole, which can make it watery instead of creamy.
Can I skip the cheddar cheese?
Yes. The casserole works without it, but cheddar adds richness and flavor depth. If omitting, increase heavy cream by 2–3 tablespoons for creaminess.
What temperature should the casserole be baked at?
The recipe uses standard oven baking. Bake at 350°F for approximately 30 minutes until bubbly and heated through, with onion topping golden.
Can I use fresh green beans instead of canned?
Yes. Use 1 pound fresh green beans trimmed and blanched 4–5 minutes, then drained well before sautéing with butter and thyme.