Grilled Portobello Mushrooms & Shallots With Rosemary-Dijon

The scent of woodsmoke always takes me back to summer evenings at my grandfather’s. He was a master of the grill, turning out simple yet unforgettable meals for the whole family. While burgers and hot dogs were staples, it was his grilled vegetables that truly captured my heart. One year, he experimented with portobello mushrooms marinated in a fragrant herb mixture, and the earthy aroma combined with the char from the grill created a flavor explosion I’ve never forgotten. These grilled portobellos, with their savory rosemary-Dijon glaze, bring back those happy memories every time I make them.

Recipe Overview

• Prep Time: 20 minutes
• Cook Time: 18 minutes
• Total Time: 38 minutes
• Servings: 4-6
• Dietary Type: Vegan, Gluten-Free

Ingredients

• 6 portobello mushrooms, about 5 inches in diameter (about 4 ounces each)
• 8 medium shallots, peeled
• 1/4 cup extra virgin olive oil, plus 3 tablespoons
• Kosher salt & fresh ground pepper
• 2 small garlic cloves, minced (about 1 teaspoon)
• 3 teaspoons lemon juice
• 2 teaspoons Dijon mustard
• 2 teaspoons finely chopped fresh rosemary

Equipment Needed

• 2 metal skewers
• Sharp knife
• Small bowl
• Whisk
• Grill

Instructions

1. Begin by preparing the shallots. Thread them through their roots and stem ends onto 2 metal skewers. This will make them easier to handle on the grill and prevent them from falling through the grates.

2. Prepare the mushrooms. Use a spoon to carefully scrape most of the gills out of the portobello mushrooms. This will create a cleaner flavor and allow the marinade to penetrate the mushroom more effectively.

3. Score the mushrooms. Using a sharp knife, cut ¼-inch slits, spaced ½ inch apart, in a crosshatch pattern on the non-gill side of the mushrooms. This helps the marinade absorb deeply and prevents the mushrooms from shrinking excessively during grilling.

4. Marinate the shallots and mushrooms. Brush the shallots and mushrooms evenly with ¼ cup of extra virgin olive oil and season generously with 2 teaspoons of kosher salt (or 1 teaspoon of table salt) and pepper to taste. Make sure to get the oil and seasoning into the slits on the mushrooms.

5. Prepare the rosemary-Dijon sauce. In a small bowl, whisk together the remaining 3 tablespoons of extra virgin olive oil, the minced garlic, lemon juice, Dijon mustard, finely chopped fresh rosemary, and ½ teaspoon of kosher salt (or ¼ teaspoon of table salt). Set this sauce aside; you’ll be using it throughout the grilling process.

6. Grill the vegetables. Preheat your grill to medium heat. Place the shallot skewers and mushrooms on the grill. Brush them with the rosemary-Dijon sauce while grilling, turning them several times, until the vegetables are tender and caramelized. This should take about 16 to 18 minutes. Be sure to move the vegetables around on the grill as needed to ensure even cooking and prevent burning. The shallots are done when they are softened and slightly charred and the mushrooms are tender.

7. Serve. Transfer the grilled vegetables to a platter. Remove the shallots from the skewers and discard any charred outer layers, if desired. Re-whisk any remaining marinade to ensure it is well combined and pour it over the vegetables. Serve immediately.

Expert Tips & Tricks

• For a deeper smoky flavor, use wood chips like hickory or mesquite in a smoker box on your grill.
• If you don’t have fresh rosemary, you can substitute 1 teaspoon of dried rosemary. Be sure to crush the dried rosemary slightly to release its flavor.
• Don’t overcrowd the grill! This will lower the temperature and steam the vegetables instead of grilling them. Work in batches if necessary.
• The size of the mushrooms affects cooking time. Smaller mushrooms will cook faster, while larger ones may require a few extra minutes. Check for doneness by piercing the mushroom with a fork; it should be tender and easily pierced.
• If your grill doesn’t have consistent heat, consider using a grill thermometer to monitor the temperature.
• The mushrooms can also be cooked indoors on a grill pan or under the broiler, but they won’t have the same smoky flavor as grilled mushrooms.

Serving & Storage Suggestions

These grilled portobello mushrooms and shallots are delicious served warm or at room temperature. They make a fantastic side dish for grilled meats, poultry, or fish. They can also be used as a vegetarian main course, served on a bed of greens or in a sandwich or wrap. Leftovers can be stored in an airtight container in the refrigerator for up to 3 days. Reheat them in a skillet over medium heat or in a 350°F (175°C) oven until warmed through. They can also be enjoyed cold. Freezing is not recommended as the texture of the mushrooms will change.

Nutritional Information

Nutrient	Amount per Serving	% Daily Value
Calories	228.5 kcal	N/A
Calories from Fat	N/A	94%
Total Fat	23.8 g	36%
Saturated Fat	3.3 g	16%
Cholesterol	0 mg	0%
Sodium	31.3 mg	1%
Total Carbohydrate	4.5 g	1%
Dietary Fiber	0.2 g	0%
Sugars	0.2 g	0%
Protein	0.7 g	1%

Nutritional information is an estimate and may vary based on specific ingredients and portion sizes.

Variations & Substitutions

• For a spicier kick, add a pinch of red pepper flakes to the rosemary-Dijon sauce.
• If you don’t have shallots, you can substitute red onion wedges. They may take slightly longer to cook, so keep an eye on them.
• Experiment with different herbs. Thyme, oregano, or sage would all be delicious additions to the marinade.
• For a balsamic glaze, whisk together balsamic vinegar and honey. Brush this over the mushrooms during the last few minutes of grilling.
• Make a complete meal by stuffing the grilled mushrooms with quinoa, roasted vegetables, or crumbled feta cheese.

FAQs (Frequently Asked Questions)

Q: Can I prepare the mushrooms and shallots ahead of time?
A: Yes, you can marinate the vegetables for up to 24 hours in advance. Store them in the refrigerator until ready to grill.

Q: What is the best way to clean portobello mushrooms?
A: Gently wipe the mushrooms with a damp paper towel to remove any dirt or debris. Avoid soaking them in water, as they will absorb it and become soggy.

Q: How do I know when the mushrooms are done grilling?
A: The mushrooms are done when they are tender and easily pierced with a fork. They should also be slightly shrunken and have grill marks on both sides.

Q: Can I use a different type of mustard?
A: Yes, you can substitute your favorite type of mustard. Stone-ground mustard or whole-grain mustard would also work well.

Q: I don’t have a grill. Can I cook these in the oven?
A: Yes, you can roast the vegetables in a 400°F (200°C) oven for about 20-25 minutes, or until tender and caramelized.

Final Thoughts

I hope you enjoy this recipe as much as I do! It’s a simple yet flavorful way to enjoy the bounty of summer. Don’t be afraid to experiment with different herbs and spices to create your own unique version. Let me know what you think and share your variations in the comments below. These grilled portobellos pair wonderfully with a crisp glass of Sauvignon Blanc or a light-bodied Pinot Noir. Happy grilling!