Cut 1/4 inch off the top of each of the garlic heads. Drizzle them with oil and sprinkle a bit of salt on each of them. 

Place the rack or steamer insert in the Instant pot and add the water.

Set the garlic heads on the rack, cut side up.

Seal the lid. Cook on high pressure for 6 to 8 minutes (6 minutes for small garlic heads, 7 minutes for medium, 8 minutes for large).

Let the pressure cooker release the pressure naturally for 5 to 10 minutes then release the rest of the pressure manually. 

While the pressure cooker is releasing pressure set the oven to broil and line a baking sheet with aluminum foil. 

When the pressure is released, transfer the garlic to the baking sheet and drizzle with a bit more olive oil. 

Broil for 4 to 6 minutes or until golden brown. 

When the garlic cools enough to handle, squeeze the bottom of each bulb and the individual cloves will pop out. 

Use in recipes right away or store in the fridge with a coat of olive oil for up to 2 weeks.