Heat a medium skillet over medium heat, melt the butter. Add the onion, celery, bell pepper, salt, and pepper and saute until the vegetables begin to soften. Remove from heat.
2 tablespoons unsalted butter, 1 cup white onion, ½ cup celery, ½ cup green bell pepper, 1 teaspoon salt, ¼ teaspoon pepper
Combine the sauteed vegetables with the green beans, corn, and mushroom mixture. Stir in the cream of celery soup, shredded cheese, and sour cream.
10 ½ ounces cream of celery soup, 1 cup sharp cheddar cheese, 1 cup sour cream
Transfer the mixture into the prepared baking dish. Top with the butter cracker crumbs and almonds (if using). Then drizzle with melted butter.
1 ½ cups butter crackers, ½ cup slivered almonds, 2 tablespoons unsalted butter
Bake for 35 to 45 minutes or until the crackers are lightly browned and the filling is bubbly. Start checking around 25 to 30 minutes just to make sure the crackers aren't getting too brown. Serve warm!
See post for tips and storage options!
Notes
*The calories listed are an approximation based on the ingredients in the recipe card and a serving size of 1 cup of casserole. Actual calories will vary.*Doubling or tripling this recipe has not been tested. Therefore, we can not guarantee the outcome of adjusting the ingredients.*For more information, tips, and answers to frequently asked questions, please refer to the post.