No, you can’t roast garlic in the pot. But you can make a pretty good approximation in a few minutes (versus an hour). True, the garlic will not “reduce” — that is, internal moisture will not condense in the cloves, making them exceptionally sweet. And they will not brown. But they will have a more intense, garlicky punch — terrific to mix with butter and spread on bread, to drop into olive oil for a few days to flavor it, to add to stews and braises for a flavor kick, or to mix into mashed potatoes for a garlicky side dish.
Pour the water into the cooker. Set a heat- and pressure-safe trivet in the pot.
Cut the top quarter off each garlic head (that is, the end toward the tip, away from the wider, flat root end), partly exposing the garlic cloves below. (Not every single clove need be exposed.)
Rub about 1⁄2 tablespoon olive oil into the cut part of the garlic head, getting the olive oil down among the cloves, particularly inside the papery skins. Set the garlic heads cut side up on the trivet in the pot. Lock the lid onto the cooker.
Optional 1Max Pressure Cooker Press Pressure cook on Max pressure for 5 minutes with the Keep Warm setting off.
Optional 2All Pressure Cookers Press Pressure cook (Manual) on High pressure for 7 minutes with the Keep Warm setting off.
When the machine has finished cooking, turn it off and let its pressure return to normal naturally, about 20 minutes. Unlatch the lid and open the cooker. Use kitchen tongs to gently pick up and transfer the garlic heads to a large plate. Cool for several minutes, then either squeeze the warm cloves out of their paper hulls; or cool to room temperature, about 1 hour, then seal the heads individually in plastic wrap and refrigerate for up to 1 week.
• For an 8-quart cooker, you must use 1 1/2 cups water.
• To brown the garlic, drizzle the cooked heads with a little more olive oil, then set them cut side up on a lipped baking sheet. Broil 4 to-6 inches from the heating element until lightly browned, 1 to 3 minutes.