Cook the diced bacon in a large skillet over medium heat until crisp.
Remove the bacon to a paper towel lined plate. Wipe excess grease from skillet.
Add the olive oil and butter to the skillet.
Add the garlic and cook 1-2 minutes, until fragrant, stirring frequently.
Stir in the chicken broth, milk, spaghetti, and pepper.
Bring to a boil.
Reduce heat and simmer, stirring occasionally until pasta is cooked through.
Stir in the reserved bacon, parmesan, sour cream, and ranch seasoning.
Top with parsley as desired.