Description
This Cheesy Asparagus Casserole is a creamy, comforting side dish perfect for spring and summer meals. Tender asparagus is cooked with sautéed onions and garlic, then enveloped in a rich, cheesy sauce made with sharp cheddar and Swiss cheese. Topped with buttery crushed Ritz crackers for a delightful crunch, this casserole can be prepared quickly in either an air fryer or conventional oven, making it a versatile and crowd-pleasing addition to any table.
Ingredients
Vegetables
- 1 bunch fresh asparagus, ends trimmed and cut into about 2” pieces
- ¼ onion, diced (yellow, sweet, or 1 shallot)
- 2 cloves garlic, minced
Dairy & Fats
- 3 Tbsp salted butter, divided
- 1 cup milk
- 1 cup shredded sharp cheddar cheese (plus extra for topping, optional)
- 1 cup shredded Swiss cheese (plus extra for topping, optional)
Dry Ingredients
- 2 Tbsp all purpose flour
- ½ cup crushed Ritz crackers
- Salt and pepper, to taste
Instructions
- Cook Onion: In a skillet, melt 2 tablespoons of butter over medium heat. Add the diced onion or shallots and cook, stirring occasionally, until softened and fragrant, about 3 to 5 minutes.
- Add Asparagus and Garlic: Add the cut asparagus pieces and minced garlic to the skillet. Cook while stirring occasionally until the asparagus turns bright green and begins to soften, approximately 6 to 7 minutes.
- Make Roux: Sprinkle the flour evenly over the asparagus and onion mixture. Stir continuously to blend the flour with the butter and vegetables, cooking until it is lightly browned, about 1 minute.
- Thicken Sauce: Slowly pour in the milk while stirring constantly to avoid lumps. Continue cooking and stirring until the sauce thickens slightly, around 2 to 3 minutes. Remove the skillet from heat.
- Add Cheese and Season: Stir in the shredded sharp cheddar and Swiss cheeses until fully melted and incorporated into the sauce. Season with salt and pepper to taste.
- Prepare Casserole Dish: Grease a casserole dish that fits inside your air fryer basket or oven. Transfer the asparagus and cheese mixture into the dish. For dual-basket air fryers, divide into two smaller dishes; otherwise, use one larger dish.
- Make Topping: In a small bowl, melt the remaining 1 tablespoon of butter in the microwave. Toss the crushed Ritz crackers with the melted butter until evenly coated.
- Top Casserole: Optionally sprinkle additional shredded cheese over the mixture in the dish. Evenly distribute the buttered cracker crumbs on top, gently pressing them into the cheese sauce to help them adhere and prevent them from flying around during air frying.
- Cook Casserole (Air Fryer): Place the dish in the air fryer and cook at 350°F on the air fry setting for 10 minutes, or until the top is golden brown and the edges are bubbling.
- Alternate Cook Casserole (Oven): Preheat the oven to 400°F and bake the casserole for about 20 minutes until the top is browned and the edges bubble. For a darker, crispier top, broil for an additional 2 to 3 minutes.
- Serve: Remove from heat and let the casserole cool for 5 to 10 minutes to allow it to thicken. Serve warm and enjoy!
Notes
- You can substitute the cheddar and Swiss cheese with other cheeses such as Gruyère or mozzarella for different flavors.
- Make sure to trim the woody ends of the asparagus to avoid unpleasant textures.
- If using a single-basket air fryer, opt for one larger casserole dish to fit comfortably.
- The casserole can be prepared ahead of time and refrigerated, then cooked just before serving.
- For a gluten-free version, substitute the all-purpose flour with a gluten-free flour blend and use gluten-free crackers.
- Adjust the seasoning with additional herbs such as thyme or parsley for added flavor.
