1Cook 1 lb of bacon cut into small pieces until crispy. Remove the bacon and set aside, reserving 1/4 cup of bacon grease.
2In the same pan, caramelize 2 sliced yellow onions and 2 sliced shallots with a pinch of salt, adding splashes of water to prevent burning. This takes about 40-50 minutes.
3While caramelizing, mix 8 oz softened cream cheese, 1 cup room temp sour cream, 1/2 cup room temp mayonnaise, 4 oz shredded sharp cheddar, 4 oz shredded mozzarella, 1 tsp Worcestershire sauce, freshly cracked pepper, and crispy bacon (save some for topping). Set aside.
4In the last 2–3 minutes of caramelizing onions, add 6 minced garlic cloves, 1-2 tsp fresh thyme, 1-2 tsp balsamic vinegar, and 1 tsp brown sugar. Stir to combine.
5Let the caramelized onions cool slightly before adding them to the cheese mixture.
6Transfer the mixture to a baking dish, top with remaining mozzarella and reserved bacon.
7Bake at 350°F for 10 minutes, then top with crispy fried onions and broil for 2-3 minutes until bubbly.