Preheat oven to 350°F.
In a large skillet over medium-high heat, cook chopped bacon until browned and crispy. Transfer bacon to a paper towel-lined plate with a slotted spoon.
In the same skillet, add ground beef and cook until browned, crumbling it as it cooks. Drain excess grease.
Stir in minced garlic and cook for 2-3 minutes.
Remove skillet from heat and stir in instant rice.
Add condensed cheddar soup, milk, and ranch dressing mix, stirring well.
Mix in 1 cup of the shredded cheese, 1 cup of the chopped green onions, and two-thirds of the cooked bacon.
Transfer mixture to a greased 9 x 13-inch baking dish, spreading evenly.
Cover with foil and bake in the oven for 40 minutes.
Remove foil, sprinkle the remaining 2 cups of cheese and cooked bacon pieces on top, and return to the oven.
Bake uncovered until the casserole is bubbling and the cheese is melted, about 5-10 minutes.
Let rest for a few minutes before sprinkling with the remaining green onions.