Hoisin Portobello Burgers with Chili-Lemon Broccolini

Mushrooms have long been a stand-in for meat-based burgers because of their substantial texture and their naturally umami-packed flavour. By adding plant-based ground round to the equation, this increases the protein to create a more satisfying and filling burger. Be sure to choose portobellos with caps that curl toward the stem. The flatter caps don’t provide a deep enough cavity to fill. Hoisin adds an incredible element of sweet richness to these epic burgers, while the unconventional but stellar topping of grilled chili-lemon broccolini adds a needed zing.

Makes 4 burgers

Ingredients

• 4 large portobello mushrooms
• 2 Tbsp. oil
• Salt
• One 12 oz (340 g) package plant-based ground round (see Tip)
• ½ tsp. onion powder
• ½ tsp. garlic powder
• ¼ cup hoisin sauce
• ¼ cup panko
• 4 hamburger buns, sliced
• 1 bunch broccolini, trimmed
• 2 tsp. oil
• 1 tsp. chili flakes
• Pinch of salt
• ½ lemon

Directions

• Use a teaspoon to gently remove the stem and brown gills on the underside of each mushroom cap. Try to keep the outer edge of the mushroom intact. Brush the mushrooms with the oil. Season the underside of the caps with salt.
• In a large bowl, combine the ground round, onion powder, garlic powder, hoisin, and panko. Divide the mixture into four equal portions and form each into a small patty. Gently press the patty into the hollow underside of each mushroom so that it fills the entire cavity. Transfer the mushroom patties to a plate, cover with plastic wrap, and chill in the fridge for at least 20 minutes or up to 24 hours.
• Preheat a clean barbecue to medium-high heat (375–400°F).
• In a large bowl, toss the broccolini with the oil, chili flakes, and season with salt.
• Grill the mushroom burgers and the broccolini at the same time. For the mushroom burgers, place patty side down on the barbecue. Grill, undisturbed, for 6–8 minutes or until the patty has set and has grill marks. Do not fuss with the burgers. Use a stainless-steel spatula to gently turn the mushrooms over, close the lid, and grill for 5–6 minutes or until the ground round is cooked through and the mushrooms are tender. Do not attempt to flip the burgers again or the filling may fall out. Transfer the mushroom burgers to a plate and set aside.
• For the broccolini, grill for 8–10 minutes, turning occasionally, until it’s tender and slightly charred. Transfer the broccolini to a cutting board and chop into 2-inch pieces. Squeeze lemon juice over top.
• Grill buns, cut side down, until toasted.
• Top the bottom half of each bun with a mushroom burger, followed by some broccolini. Add your desired toppings such as ketchup, mayonnaise, sliced pickles, and sliced red onions, and cover with the top half of the bun. Dig in. Leftovers will keep in an airtight container in the fridge for up to two days.

Nutrition facts per serving
Calories 550; protein 23 g; fat 125 g; carbs 60 g. 

Photography By: Lori Rasmusssen

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Read This Story in Our 2026 Summer & Outdoor Issue

Canada’s best source of health & fitness information — IMPACT Magazine’s 2026 Summer Outdoor Travel Issue: trail running, outdoor travel, workouts and seasonal recipes.

Featuring world-class French-Canadian ultra-trail runner Mathieu Blanchard, this digital edition takes you coast to coast through Canada’s most unforgettable bucket-list hikes, trail-running tips, and race-day strategies. Build strength and balance with targeted summer workouts, master the taper, and find your footing on technical terrain. Plus enjoy seasonal grilling and plant-forward recipes — Grilled Mexican Corn, Hoisin Portobello Burgers with Chili Lemon Broccolini, Smoky Black Bean Quinoa Burgers — and more outdoor cooking inspiration for active travelers.