Portabella Mushroom Sliders – Canadian Style

Canadian mushrooms, Quebec Oka Cheese, Maple Caramelized Onions, and Canadian Bacon make these Portobello sliders deliciously patriotic.
Course Appetizer
Cuisine Canadian
Prep Time 15 minutes
Cook Time 45 minutes
Total Time 1 hour
Servings 8 servings
Calories 197 kcal
Author Colleen


Maple Caramelized Onions

  • 2 tbsp olive oil
  • 3 large onions sliced into 1/8" slices
  • 3 tbsp maple syrup
  • 2 tbsp balsamic vinegar


  • 8 mini portabella mushrooms
  • 2 tbsp olive oil
  • 1 tbsp balsamic vinegar
  • salt & pepper
  • 8 slices Oka cheese or enough to cover mushrooms
  • Eight slider buns
  • Dijon mustard
  • Mayonnaise
  • 8 slices back bacon sliced into strips
  • 8 bib lettuce leaves trimmed for slider buns


Maple Caramelized Onions

  1. Heat the oil in a large skillet over medium high heat
  2. Add the onions and cook, stirring, until starting to soften.
  3. Stir in 1/2 cup water & bring to a boil.
  4. Reduce heat to medium low and simmer until most of the liquid has disappeared.
  5. Stir in another 1/2 cup water, and continue cooking 30-40 minutes, adding more water when needed.
  6. Stir in maple syrup and balsamic vinegar.
  7. Cook, stirring until onions are brown and most of the liquid has evaporated.
  8. Remove from heat and set aside


  1. Wash mushrooms and remove stems.
  2. Put mushrooms in a shallow dish and whisk together olive oil, vinegar, salt and pepper.
  3. Pour olive oil mixture over mushrooms, turning to coat
  4. Allow to sit for 30 minutes while onions are cooking.
  5. Oil grill with cooking spray and heat to medium high.
  6. Grill mushrooms covered, about 5 minutes each side
  7. During the last minute of grilling, top each mushroom, stem side with cheese. Cover and heat until cheese is melted. Remove from grill.
  8. While mushrooms are grilling assemble the slider buns by spreading each with Dijon mustard and mayonnaise on each of the halves.
  9. Top the bottom halves with lettuce, bacon, and caramelized onions.
  10. Add the cheese topped mushrooms, and top with the other half of the slider bun.

Recipe Notes

This recipe makes a one pint jar of Maple Caramelized Onions, and you will only use a portion of it for these sliders, so you'll have extra on hand to store in the fridge and use as a delicious condiment.

Many of the steps in the recipe are simultaneous, so you can do a lot of the prep work while the onions are caramelizing and the mushrooms are grilling.

Nutrition Facts
Portabella Mushroom Sliders – Canadian Style
Amount Per Serving (1 slider)
Calories 197 Calories from Fat 99
% Daily Value*
Fat 11g17%
Saturated Fat 3g15%
Cholesterol 21mg7%
Sodium 313mg13%
Potassium 527mg15%
Carbohydrates 14g5%
Fiber 1g4%
Sugar 9g10%
Protein 10g20%
Vitamin A 565IU11%
Vitamin C 3.6mg4%
Calcium 78mg8%
Iron 0.8mg4%
* Percent Daily Values are based on a 2000 calorie diet.