Foods & cuts · Portobello mushroom
Portobello mushroom
A flat cap that sits on the grate unaided, eight to fifteen minutes depending on the source. The vegetable most often used as a burger substitute, which is why the form matters.
What it is
- Form
- Whole mushroom
- Typical weight
- 60–120 g
- Typical thickness
- 20–30 mm
- Cut
- Not a cut of anything
Why it behaves as it does
Iowa State gives eight to nine minutes smooth-side-down; North Dakota State gives twelve to fifteen. It is the same species as a button mushroom grown to full size, and BBQHQ keeps them as separate foods for exactly that reason — the cap is flat, stable and roughly twice the time, so transferring a button mushroom's figure to it would be wrong in both directions. Gills up after the first turn holds the liquid it releases rather than dropping it into the fire.
When is it done?
Food-safety endpoint
BBQHQ holds no food-safety rule for this food. We are not showing you another jurisdiction’s figure in its place — check your national food-safety authority.
Texture endpoint — how you actually know
Softened through, gills dark and wet
The cap yields in the middle and the gills have darkened. A portobello holds a surprising amount of liquid; turning it gills-up after the first turn keeps that in the mushroom rather than in the fire.
How long it takes
Portobello mushroom, grilled
Estimated cooking window
12 min–15 min
Moderate confidence
Why this is a range, not a number
- Cookers hold temperature imperfectly
- Individual animals and pieces differ
Cook to the endpoint, not to the clock. The window tells you when to start checking.
What this rests on
BBQHQ publishes a window for this cook.
- Observations
- 2
- Documents
- 2
- Publishers timing this cook
- 2
Iowa State University Extension and Outreach · North Dakota State University Extension
Why confidence is not higher
- At least one source does not state the cooker temperature.
How the sources were combined
TWO INDEPENDENT LAND-GRANT EXTENSION SERVICES, AND THEY DO NOT QUITE AGREE. North Dakota State gives 12–15 minutes as a total; Iowa State gives 8–9 minutes per side, which is 16–18 if the food is turned once. BBQHQ publishes the NDSU total because it is stated as a total and needs no arithmetic from us, and keeps the Iowa State figure beside it rather than averaging the two into a number neither publisher wrote. Where they differ they differ about arrangement — cut, heat and turning — rather than about the vegetable.
What makes the window as wide as it is
- Cookers hold temperature imperfectly
- Individual animals and pieces differ
When it goes wrong
- It went watery or soggy
- Vegetables went soggy instead of browning — 2 distinguishable causes.
- It never browned
- Vegetables went soggy instead of browning — 2 distinguishable causes.
Afterwards
Cooling, keeping and reheating what is left is general guidance for barbecue leftovers. Neither UK authority publishes anything specific to portobello mushroom, and BBQHQ does not invent a distinction they do not make.