- 1 tablespoon butter, or more to taste
- 1 tablespoon vegetable oil
- 1/2 fennel bulb, sliced
- 1 onion, sliced
- salt and ground black pepper to taste
- Heat butter and oil in a skillet over medium heat until butter is melted, about 1 minute. Add fennel to skillet; cook and stir until beginning to soften, about 5 minutes. Add onion; season with salt and pepper. Cook and stir until onion is translucent and fennel is tender, 5 to 7 minutes.