In an 8" oven-safe nonstick skillet, heat olive oil on medium. Add bacon and shallot; cook 6 minutes, stirring occasionally. Whisk eggs, milk, salt, and pepper until combined; stir in Gruyère. Add eggs to skillet. Cook 3 minutes, stirring occasionally to form curds and allow runny egg to flow to bottom of pan. Bake at 375 degrees F for 8 minutes or until top is set. Garnish with chives. Serve with green salad.