Grilled Mushroom and Olive Tapenade Sandwiches

Recipe and photo by Tami Ganeles Weiser Yield:  7 servings (14 sandwiches total)
Prep Time:  30 minutes Cook Time:  20 minutes

Grilled Mushroom and Olive Tapenade Sandwiches

They may look like little whoopie pies, but these mushroom appetizers are born to be served with an ice-cold martini or a glass of chilled Sauvignon Blanc. Care to experiment? Try them with a little ouzo, a brisk Gewürztraminer or a brisk Provençal rosé.


1 pound Portobello mushrooms (about 14 to 16 mushrooms)

1 medium zucchini

2 tablespoons extra-virgin olive oil

½ teaspoon kosher salt

1½ cups chopped walnuts, preferably toasted

2 tablespoons drained capers

5 white anchovy fillets (or 2 traditional, canned or jarred in oil)

½ teaspoon fresh thyme leaves

½ teaspoon fresh oregano leaves

1 teaspoon white wine vinegar

Zest of 1 lemon (about 1 teaspoon)

½ cup red, green, or black Cerignola olives, pitted

½ cup black Niçoise olives, pitted

1 cup black Kalamata olives, pitted

1 cup green olives, Castelvetrano preferred 

½ teaspoon freshly ground black pepper

Chopped walnuts, for garnish (optional)


  1. Cut off the stem of each mushroom, leaving only the cap (portobellos don’t usually have much stem, anyway). Using a spoon, scoop out the black ribs from the inside of the mushroom cap.
  2. Cut the zucchini lengthwise, into ½ inch thick slices. Brush the mushrooms and zucchini on both sides with the olive oil.
  3. Heat a grill to high. Grill the zucchini until soft and pliable but not mushy; then remove from the grill and set aside. Sprinkle the mushrooms with salt and grill for 2 to 3 minutes on each side, until browned on the edges and very soft in the middle. While those cook, finish the tapenade filling.
  4. Add the zucchini and walnuts to the bowl of a food processor and pulse until smooth and creamy. Add the capers, anchovies, thyme, oregano, vinegar, and lemon zest and process, pulsing, until just blended.
  5. Add all of the olives and pulse until the mixture is well combined but still contains fairly coarse chunks of olives.
  6. Place the mushroom on a serving plate, hollow side up. Fill each with the tapenade. (You can use as much or as little as you like.) Cover with another mushroom. Cut in quarters, or for smaller mushrooms, in half, and serve. Garnish with additional chopped walnuts, if desired, by rolling the edge in the nuts.

Kitchen Tips

  1. Covered and refrigerated, this will last about 2 days.
  2. Castelvetrano olives are meatier and milder than your typical olive. They can be found at at specialty stores.
  3. If you are using a grill pan, you can also grill the white anchovies lightly to get a bit of a char.
  4. If you want to make this a vegan entree, omit the anchovies and add 1 teaspoon nutritional yeast, double the pepper, and add 1 teaspoon smoked salt.

Leave a Comment

All fields are required. Your email address will not be published.