hamburger casserole recipe

### Ingredients: - **1 pound** ground beef - **1 small onion**, chopped - **1 can** (10.75 ounces) condensed tomato soup - **1 can** (10.75 ounces) condensed cream of mushroom soup - **1/2 cup** milk - **2 cups** shredded cheddar cheese, divided - **2 cups** frozen mixed vegetables (like peas, carrots, and corn) - **4 cups** cooked egg noodles - **Salt and pepper**, to taste