Mom's traditional creamed onions recipe uses pearl onions, butter, milk, and flour to create creamy goodness on the stovetop; it's an easy, tasty side.
Boil water in a medium saucepan over medium-high heat. Add onions and cook until tender; drain, reserving 2 cups of cooking liquid. Set onions and liquid aside.
Melt butter in the same saucepan over medium heat; whisk in flour to make a paste. Whisk milk into reserved cooking liquid; slowly add milk mixture to the saucepan, whisking constantly. Cook until thickened.
Season with salt and pepper; stir in onions and transfer to a serving dish.