Preheat oven to 375°
Cover a rimmed baking sheet with foil or parchment paper for easy clean-up.
Heat Olive Oil in a small skillet over medium heat and sauté onion and peppers until they just start to soften.
Add garlic to pan, sauté for a minute and remove the pan from the heat to cool.
Put the Ground Beef in a large bowl.
In a smaller bowl, mix the egg, milk, breadcrumbs, Worcestershire Sauce, Parsley, Italian Seasoning, Salt, and Pepper.
Combine Beef and ingredients from the smaller bowl together.
Shape into a loaf on the prepared baking sheet
Bake for 50 minutes.