How Long to Bake Portobello Mushroom at 350

Are you looking for a healthy appetizer, side dish, or vegan main course? 

Baked Portobello mushroom is an ideal choice, which is super delicious and easy to make. 

However, you will need to get it right on temperature and timing when baking Portobello mushrooms in an oven. 

How Long to Bake Portobello Mushroom at 350

Baking Portobello mushroom at 350 degrees Fahrenheit in the oven takes around 25 to 30 minutes.  Although the 350 degrees won’t hurt, the ideal temperature to bake Portobello mushrooms is 400 degrees Fahrenheit. This way, you will only need to bake for 15 to 20 minutes. 

But that’s not all that you need to know about baking Portobello mushrooms. This recipe comes with so much in it. Read on to discover more.

What We Love About Baked Portobello Mushroom

  • Portobello mushroom is so delicious
  • You can use your preferred seasoning 
  • You only need 15 minutes to marinate before baking
  • You can pair it with almost all kinds of dishes
  • The mushroom is super-healthy as it is low in calories and loaded with nutrients.
  • You can use it as a vegan side or main dish
  • You can make it keto, gluten-free, or paleo

How to Cook Portobello Mushroom in the Oven?

Portobello mushroom is pretty quick and easy to prepare. These mushrooms are the best when marinated and then baked.


  • Two large Portobello mushrooms
  • 1/2 tbsp. olive oil
  • 2 tbsp. soy sauce, you can also substitute with tamari or coconut aminos
  • 1/2 tsp. minced garlic
  • 1/4 tsp. minced or grated ginger root
  • 1 tbsp. balsamic vinegar

You can also use salt, cayenne pepper, thyme, rosemary, maple syrup, and crushed garlic.


  1. Clean Your Portobello Mushrooms

Wipe the mushrooms with a clean, damp kitchen towel. You can use a mushroom cleaning brush to get rid of stubborn dirt. Scrub the cap and gills gently but be careful not to remove the gills. They add extra juiciness and enhance flavor. 

Rinsing mushrooms or running them in a lot of water makes them mushier and ruins the expected results.

Start by removing the mushroom stem. You can cut it off with a knife or twist it off. Do not throw away the stem. It comes in handy when stuffing your mushrooms.

  1. Preheat your oven to 350 degrees Fahrenheit
  2. Create Your Seasoning Sauce

Take a large bowl, add all the ingredients you are using except mushrooms, and whisk them together to make a marinade sauce.

  1. Place your clean Portobello mushrooms on a baking tray with parchment paper. 

Brush your marinade sauce onto the mushrooms, ensuring that all sides are well-coated.

Set the mushrooms aside and let them rest for 15 minutes.

  1. If you have some sauce left, rub it on the mushrooms before placing them in the oven. 

Bake for 20 minutes until you have a nice brown color. 

  1. Remove the mushrooms from the oven. Let them cool down before slicing and serving.
  2. Stuff Your Portobello Mushrooms (Optional)

If you want your mushrooms to be fuller, allow them to cool down and then stuff them with your preferred ingredients. 

You can use the stems you set aside or use cheese, parmesan, or mozzarella. Toast them back in the oven for five more minutes to allow the cheese to melt.

The Secret to Making Perfect Portobello Mushrooms

Choose huge, fresh Portobello: If you cannot access big Portobello, it is advisable to double the sauce and the Portobello caps to ensure you have enough servings. 

Always use parchment paper or foil to lay your mushrooms. If not, soak your baking pan immediately after cooking. 

Do not slice the mushrooms straight from the oven. Let them rest a bit so that they retain the juices and flavors.

Don’t be afraid to spice up your mushrooms. Spices make them appealing and tasty.

What Goes with Portobello Mushrooms?

Portobello mushrooms are already yummy on their own. However, you can level them up with different stuffing to make them even more exciting and delicious.


Instead of using plain cheese, which is a standard stuffing, why not try bacon and cheddar or feta cheese and tomatoes?

Steak or Veggies

Steaks and other meats are fantastic accompaniments to Portobello mushroom if you are serving it as a side dish or appetizer.

To make the main meal, you can pair mushrooms with cauliflower salad, broccoli, and other greens.


Baked mushrooms can also serve as burger patties. Then, top it up with cheese, tomatoes, and basil.

  • Rice – You can serve it over rice and season with your favorite sauce
  • Prime rib roast
  • Smoked brisket
  • Baked asparagus
  • Noodles with peanut sauce
  • Grilled zucchini

Portobello Mushroom Nutritional Facts

Vitamin A160IU
Vitamin C0.3mg
Potassium 337mg
Sodium 146mg

How to Store Leftover Mushroom

Put the leftovers in an airtight container and store them in the refrigerator for up to 3 days.

Frequently Asked Questions

How do you know when a Portobello mushroom is cooked?

When you press the middle of your mushroom with tongs, it should feel very soft and juicy. It takes about 10-20 minutes, depending on your mode of cooking and the size of your Portobello. 

Do you eat the gills of a Portobello mushroom?

Yes, a Portobello mushroom’s dark, black gills are edible and nutritious. They are juicy and add flavor to the mushroom.

What other ways can you cook Portobello mushrooms instead of baking?

You can cut your mushrooms into small pieces and sauté them in a pan. This process takes about 10 minutes. You can also roast or grill the mushrooms for 5 minutes on each side, then season with some salt, garlic, oil, and vinegar for a tastier outcome.

How do you soften Portobello mushrooms?

You can soften your mushrooms ahead of cooking by simmering them in a mixture of salt and water for some minutes. This way, they will soften faster when baking.


Baked Portobello mushroom is an incredible meal to entertain your family and guests. You can stuff it with your preferred ingredients, top it with your favorite sauce and serve it alongside your chosen meal. 

Baking Portobello mushroom at 350 degrees takes about 25 to 30 minutes. 

Avatar for Joy
About Joy

Hi, I'm Martin and my friends call me Joy. From an early age, I was interested in food, vegetables, and fruits. I even have a nutritionist certificate. While searching for some information, I didn't find the answer, so I start a page

Leave a Comment