Mushroom Sandwich with Pickled Onion


This sandwich is a specialty at Dad's Luncheonette in Half Moon Bay, California, where chef-owner Scott Clark makes it with local maitake mushrooms. Using ghee to cook the sandwich components imparts a nutty flavor you wouldn't get by using butter.

Dad’s Mushroom Sandwich
Photo: Eric Wolfinger
Active Time:
55 mins
Total Time:
5 hrs
Nutrition Profile:


Pickled Onion

  • 1 ½ tablespoons crushed red pepper

  • 1 tablespoon whole black peppercorns

  • 1 clove garlic, smashed and peeled

  • 1 bay leaf

  • 1 cup white balsamic vinegar

  • 1 cup granulated sugar

  • 1 medium red onion, thinly sliced


  • 3 tablespoons mayonnaise

  • 1 tablespoon spicy brown mustard

  • 1 teaspoon vegetarian Worcestershire sauce

  • 5 tablespoons ghee, divided

  • 8 slices whole-wheat bread

  • 14 ounces maitake mushrooms

  • ¼ teaspoon ground pepper

  • teaspoon salt

  • 4 slices sharp Cheddar cheese

  • 4 large eggs

  • 8 lettuce leaves, preferably red oak


  1. To prepare pickled onion: Toast crushed red pepper, peppercorns, garlic and bay leaf in a medium saucepan over medium-low heat until fragrant, 1 to 3 minutes. Add vinegar; bring to a boil over medium-high heat. Add sugar and stir until dissolved. Place onion in a medium non-reactive bowl and pour the hot liquid over it. Let cool to room temperature, about 1 hour. Cover and refrigerate for 4 hours and up to 1 week.

  2. To prepare sandwich: Combine mayonnaise, mustard and Worcestershire in a small bowl.

  3. Heat 1 tablespoon ghee in a large nonstick skillet over medium-high heat. Add 2 to 3 bread slices and cook until browned on one side only, 1 to 2 minutes, adjusting heat as necessary. Transfer to a plate. Repeat 2 more times with 2 tablespoons ghee and the remaining bread.

  4. Add mushrooms, pepper, salt and 1 tablespoon ghee to the pan. Cook, without stirring, until browned and crisp, 2 to 3 minutes. Flip the mushrooms and press with a spatula to flatten. Top with cheese and cook until it is melted, about 3 minutes more. Transfer to a plate.

  5. Add the remaining 1 tablespoon ghee to the pan over medium heat. Crack eggs into the pan, cover and cook to desired doneness, 2 to 4 minutes.

  6. Spread the sauce on the untoasted sides of the bread. Layer the pickled onion, mushrooms, eggs and lettuce between the bread slices.

To make ahead

Refrigerate pickled onion (Step 1) for up to 1 week.

Nutrition Facts (per serving)

623 Calories
38g Fat
51g Carbs
21g Protein
Nutrition Facts
Servings Per Recipe 4
Serving Size 1 sandwich
Calories 623
% Daily Value *
Total Carbohydrate 51g 19%
Dietary Fiber 7g 25%
Total Sugars 21g
Protein 21g 42%
Total Fat 38g 49%
Saturated Fat 17g 85%
Cholesterol 252mg 84%
Vitamin A 733IU 15%
Sodium 674mg 29%
Potassium 536mg 11%

Nutrition information is calculated by a registered dietitian using an ingredient database but should be considered an estimate.

* Daily Values (DVs) are the recommended amounts of nutrients to consume each day. Percent Daily Value (%DV) found on nutrition labels tells you how much a serving of a particular food or recipe contributes to each of those total recommended amounts. Per the Food and Drug Administration (FDA), the daily value is based on a standard 2,000 calorie diet. Depending on your calorie needs or if you have a health condition, you may need more or less of particular nutrients. (For example, it’s recommended that people following a heart-healthy diet eat less sodium on a daily basis compared to those following a standard diet.)

(-) Information is not currently available for this nutrient. If you are following a special diet for medical reasons, be sure to consult with your primary care provider or a registered dietitian to better understand your personal nutrition needs.

Related Articles