Cook pasta on the stove according to package instructions. Drain and set aside.
Using sauté mode, cook chopped bacon in the pressure cooker until crispy. Remove and drain on paper towel.
In the same pot, brown the ground beef, breaking it apart as it cooks. Drain excess grease.
Add diced onion and minced garlic to the beef. Sauté 3-4 minutes until softened.
Lower heat and stir in cream cheese, milk, ketchup, and mustard. Stir until smooth and creamy.
Add cooked pasta and crispy bacon back into the pot. Stir to combine.
Sprinkle in shredded cheddar and mix until fully melted and creamy.
Season with salt and pepper to taste. Optionally garnish with chopped green onions.
Seal the pressure cooker and cook briefly to warm through, using quick release to prevent overcooked pasta.
Notes
Using pre-cooked bacon speeds things up. Leftovers keep well in the fridge for 3-4 days or freeze for later. Reheat with a splash of milk for creaminess.