Melt Butter: In a 2-quart saucepan, melt 2 tablespoons of butter over low-medium heat.

Cook the Onions: Add the thinly sliced onions and cook, stirring frequently, until they are soft and transparent but not browned, about 7 to 15 minutes.

Add Chicken Broth: Pour in the chicken broth.

Add Seasonings: Stir in the chicken bouillon cubes, ¼ teaspoon salt, and ¼ teaspoon freshly ground black pepper. Stir well to combine.

Melt Butter (White Sauce): In a separate 1-quart saucepan, melt 3 tablespoons of butter over medium heat.

Make the Roux: Add the flour, stirring constantly to create a roux. Continue to cook for 2-3 minutes until the mixture thickens and begins to pull away from the sides of the pan.

Add Milk: Gradually add 1½ cups of whole milk, stirring continuously to avoid lumps. Continue stirring until the sauce thickens to a pudding-like consistency.

Season (White Sauce): Add ¼ teaspoon salt and mix thoroughly. Remove from heat and set aside until ready to use.

Mix White Sauce: Add the prepared white sauce to the onion and broth mixture in the 2-quart saucepan.

Add Velveeta Cheese: Stir in the diced Velveeta cheese. The soup will thicken as the white sauce and cheese combine, so continue stirring until the cheese is fully melted and the soup is creamy, about 10 to 15 minutes on medium-low heat.

Simmer the Soup: Reduce the heat and allow the soup to cook for an additional 30-45 minutes, letting the flavors fully infuse. Stir occasionally to prevent the soup from sticking to the bottom of the saucepan.

Ladle the Soup: Serve the hot soup in bowls.

Garnish: Top with shredded cheddar cheese for extra cheesiness.

Serve with Bread: Enjoy with warm dark Russian bread slices on the side to balance the richness of the soup.