Wash cauliflower and cut into evenly-sized florets.
Place florets in the Instant Pot insert.
Pour in 1 cup of water.
Secure the lid and set the valve to sealed. Select “Manual” or “Pressure Cook” on high pressure for 3 minutes.
When cooking is complete, carefully quick release the pressure.
Drain the water thoroughly, pressing gently to remove excess moisture.
Add butter, garlic, salt, pepper, and heavy cream to the cauliflower.
Mash with a hand masher for chunky texture or use a hand mixer for ultra-smooth, creamy results.
Taste and adjust seasoning. Garnish with fresh parsley and serve immediately.