How many servings does this recipe make?

This recipe makes 4 servings. You can adjust the portion size directly on this page.

What ingredients do I need for Easy Cheesy Brunch Casserole?

You need 12 ingredients. The key ingredients include: 4 slices white sandwich bread, 1 medium onion, chopped, 1 c. sliced fresh mushrooms, 2 Tbsp. butter or margarine, melted, and more.

Is Easy Cheesy Brunch Casserole suitable as breakfast?

Yes, Easy Cheesy Brunch Casserole falls under the Breakfast category and is a great choice for this type of meal.

How do I store leftover Easy Cheesy Brunch Casserole?

Store leftovers in an airtight container in the refrigerator for up to 3–4 days. Reheat gently before serving.

Easy Cheesy Brunch Casserole Recipe

Name: Easy Cheesy Brunch Casserole
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4 servings
Ingredients: 4 slices white sandwich bread; 1 medium onion, chopped; 1 c. sliced fresh mushrooms; 2 Tbsp. butter or margarine, melted; 1 c. chopped, cooked ham; 1 c. (4 oz.) shredded Cheddar cheese; 1 c. (4 oz.) shredded Swiss cheese; 1 Tbsp. all-purpose flour; 1 1/4 c. milk; 4 large eggs, beaten; 1 Tbsp. prepared mustard; 1/2 tsp. garlic salt

Start your day right with this Easy Cheesy Brunch Casserole recipe. Made with white sandwich bread, onion, mushrooms and butter. Easy step-by-step instr…

This Easy Cheesy Brunch Casserole relies on simple, everyday ingredients such as white sandwich bread, medium onion, chopped, sliced fresh mushrooms and butter or margarine, melted. It comes together quickly and makes 4 servings, at about 857 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.

It's an easy way to start the day, whether you're cooking a relaxed weekend breakfast or need something satisfying before a busy morning. Pair it with fresh fruit or your favorite hot drink to round out the meal.

Updated Jun 30, 2026

Serves 4 Breakfast

Tips for the best results

Read through all the steps once before you start and measure out your ingredients first — it makes everything go more smoothly.
Taste as you go and adjust the seasoning before serving.
Avoid overcrowding the pan — cook in batches if needed for the best texture.
Let the dish rest for a few minutes before serving so the flavors settle.
Store leftovers in an airtight container in the fridge and enjoy within a few days.

Variations & substitutions

Use a neutral oil or a plant-based spread in place of butter for a dairy-free version.
A good 1:1 gluten-free flour blend works well if you need a gluten-free version.

No specific allergen information. Please check the ingredient list for possible allergens.

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Easy Cheesy Brunch Casserole

Tips for the best results

Variations & substitutions

My Personal Notes

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