Cook bowtie pasta according to package instructions. Drain and set aside.
In a large skillet, heat olive oil over medium heat. Add diced onion and cook until softened.
Add garlic and sauté for 1 more minute.
Add ground beef and cook until browned. Drain any excess fat.
Stir in diced tomatoes with green chilies and cook for 2-3 minutes.
Reduce heat to low, add milk and Velveeta cheese cubes. Stir until cheese is completely melted and sauce is smooth.
Add the cooked pasta and mix well to coat.
Season with salt and pepper to taste. Garnish with chopped parsley if desired. Serve hot.