Melt 4 tablespoons butter and heat 1 tablespoon olive oil in a skillet over medium heat. Cook and stir the mushroom slices in the skillet until tender. Remove pan from heat and set aside.
3
Melt 1 tablespoon butter and heat 1 tablespoon olive oil in a saucepan over medium-high heat. Stir in the garlic and cook until tender, then gradually whisk in 1 tablespoon flour. Cook, stirring constantly, for 1 minute.