Preheat the oven to 350°F (175°C).

In a small skillet, heat olive oil over medium heat. Add the diced onion and bell pepper, sautéing for approximately 5 minutes until softened. Remove from heat and set aside to cool.

In a large bowl, combine the whisked eggs, crushed Ritz crackers, sautéed onions, bell peppers, shredded cheddar cheese, milk, salt, and black pepper. Stir until well mixed.

Add the ground beef to the bowl and mix gently until all ingredients are just incorporated. Be careful not to overwork the meat to maintain a tender texture.

Shape the meat mixture into a loaf and transfer it to a loaf pan. Using a loaf pan ensures the meatloaf holds its shape and cooks evenly.

Bake for 30 minutes.

While the meatloaf is baking, prepare the topping by combining the ketchup, brown sugar, and yellow mustard in a small bowl.

After 30 minutes, remove the meatloaf from the oven and brush the topping evenly over the surface. Return it to the oven and bake for an additional 30-40 minutes, or until the internal temperature reaches 155°F.

Once the meatloaf has finished cooking, let it rest in the pan for 15 minutes. This resting period allows the temperature to rise by 8-10°F and ensures the juices are retained. Check that the internal temperature has reached 160°F before slicing.