Savory Portobello Mushroom Lettuce Cups Recipe – Low-Carb

Portobello Lettuce Cups

Ingredients

• ¼ cup coconut aminos
• 1 teaspoon fish sauce
• ½ teaspoon toasted sesame oil
• 1 tablespoon rice vinegar
• ½ teaspoon ground ginger (or fresh grated ginger, optional)
• 2 teaspoons arrowroot or tapioca flour
• 5 large portobello mushroom caps, diced
• 3 tablespoons avocado oil (or neutral oil of choice)
• 1 large shallot, diced small
• 2 cloves garlic, minced
• 1 teaspoon kosher salt
• 1 large fresno chile, very thinly sliced (or substitute jalapeño)
• 1 (8-ounce) can water chestnuts, drained and roughly chopped
• ¼ cup loosely chopped cilantro leaves
• Butter lettuce leaves, for serving

Instructions

1. In a small bowl, whisk together the coconut aminos, fish sauce, toasted sesame oil, rice vinegar, ground ginger, and arrowroot until smooth. Set the sauce aside so the arrowroot can hydrate briefly.
2. Heat a large nonstick skillet over medium-high heat and add the avocado oil. When the oil is hot, add the diced shallot and minced garlic. Cook, stirring, until the shallots become just tender, about 2 minutes. Keep an eye on the garlic so it does not brown.
3. Add the diced portobello mushrooms to the skillet along with the kosher salt, thinly sliced fresno chile, and chopped water chestnuts. Cook, stirring occasionally, until the mushrooms release their moisture and become tender, about 3 to 4 minutes.
4. Pour the prepared sauce into the pan and stir to combine. The arrowroot will quickly thicken the sauce; cook for about 1 minute more, until the sauce coats the mushrooms and everything is heated through.
5. Remove the skillet from the heat and stir in the chopped cilantro.
6. Spoon the mushroom mixture into butter lettuce leaves and serve immediately. Enjoy as handheld cups or serve over cauliflower rice for a heartier option.

Tips and Variations

To make this dish vegan, replace the fish sauce with a splash of tamari or an extra tablespoon of coconut aminos and a pinch of sea salt for depth of flavor. If you prefer a milder chili kick, remove the seeds from the fresno chile or substitute with a mild pepper. For a smoky element, add a teaspoon of smoked paprika or use a splash of tamari mixed with a little maple syrup for a sweeter glaze.

If you don’t have arrowroot or tapioca flour, you can use cornstarch in the same amount to thicken the sauce. For extra texture, stir in a handful of chopped toasted cashews or peanuts before serving. Fresh herbs like Thai basil or mint can be used in place of cilantro for a different flavor profile.

Make-Ahead and Storage

The mushroom filling can be prepared up to two days in advance and refrigerated in an airtight container. Reheat gently in a skillet over low heat, adding a splash of water if needed to loosen the sauce. Assemble the lettuce cups just before serving so the leaves stay crisp. Leftovers will keep in the refrigerator for 3–4 days.

Serving Suggestions

These lettuce cups make a great appetizer for a party or a light weeknight dinner. For a complete meal, serve them with a side of cauliflower rice, steamed broccoli, or a simple cucumber salad. They also pair well with a citrusy dipping sauce or a drizzle of sriracha for extra heat.