Instant Pot Caprese Garlic Butter Portobellos

These tantalizingly tasty garlic butter portobellos are packed with melty mozzarella, juicy tomatoes, ribbons of fresh basil and drizzled with savory-sweet balsamic glaze.  They are gluten-free, low-carb and go start-to-fork in only 20 minutes thanks to the Instant Pot (get yours here:

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Garlic buttered mushrooms are one of the best inventions by man, and pairing them with classic caprese flavors is simply genius. I love the large portobello mushroom caps because you can basically stuff them with almost anything and the result is a beautiful meal that you created in no time–in this case a melty caprese salad inside of a portobello mushroom cap!

Caprese, the classic mix of tomatoes, sweet basil and fresh mozzarella, is one of my favorite flavor combinations. Whether it’s a fresh caprese salad with beefsteak tomato slices layered with fresh buffalo mozzarella, a delicious wood-fired Margherita pizza, or our Delightful Caprese Chicken, this flavor combo can’t be beat!

Pro Tip: If you cannot find a prepared balsamic glaze, make your own by combining 1 cup balsamic vinegar with 1/4 cup brown sugar and simmering until reduced by half.

Make a melty caprese salad inside a portobello mushroom cap.


  • 2 tbsp butter, melted
  • 1 tsp garlic powder
  • 2 tsp finely minced parsley
  • 3 3-4” diameter portobello mushrooms, stem removed
  • 6 cherry or grape tomatoes, halved
  • 3 oz pearl mozzarella (or other small mozzarella cut into 1/2″ pieces
  • 1 cup water
  • Balsamic glaze
  • 1 tbsp fresh basil, cut into ribbons


  1. In a small bowl, melt butter. Add garlic powder and minced parsley and stir to combine.
  2. Brush both sides of the portobellos with the garlic butter and arrange in a steamer basket, stem side up.
  3. Divide the tomato halves and mozzarella among the mushrooms.
  4. Pour one cup of water in the Instant Pot and insert the steam rack. Carefully lower the steamer basket on to the steam rack.
  5. Secure the lid, making sure the vent is closed.
  6. Using the display panel select the MANUAL function*. Use the +/- keys and program the Instant Pot for 10 minutes.
  7. When the time is up, quick-release the pressure.
  8. Carefully remove the mushrooms from the pot. Drizzle with balsamic glaze and top with basil ribbons.
  9. Serve warm.

*The MANUAL and PRESSURE COOK buttons are interchangeable.