Lightly spray the bottom and sides of a 3–4 quart slow cooker with non-stick spray.
Slice the cream cheese into cubes and add to the bottom of the crockpot.
16 ounces cream cheese
Add sour cream, mayonnaise, both cheeses, garlic powder, onion powder, jalapeños, and half the crumbled bacon (reserving the rest for topping after cooking).
1 cup sour cream, 1/2 cup mayonnaise, 1 ½ cups shredded sharp cheddar cheese, 1 cup shredded Monterey Jack, 1 teaspoon garlic powder, 1 teaspoon onion powder, 4 fresh jalapeños, 4 slices bacon
Stir together.
Cover and cook on LOW for 1½–2 hours, stirring every 30–40 minutes so nothing sticks to the bottom and all the cheeses melt evenly.
Once hot, smooth, and fully melted, sprinkle the reserved bacon and chopped green onions on top.
4 slices bacon, 2–3 Tablespoons chopped green onions
Serve straight from the slow cooker or transfer to a serving dish with chips, crackers, veggies, or sliced baguette.