Preheat your oven to 400°F (200°C). Slice the top off the garlic bulb, drizzle with olive oil, sprinkle with salt, wrap in foil, and roast for 40-50 minutes until soft.

Peel and cube the potatoes. Place them in a pot with cold water, add onion, smashed garlic, bay leaf, and kosher salt. Bring to a boil and cook for 30-40 minutes until tender.

Drain potatoes and return to pot, discarding bay leaf. Mash thoroughly on low heat to release steam.

Squeeze the roasted garlic into the pot. Add butter, cream cheese, and half-and-half. Mash until smooth, and season with seasoning salt and black pepper.

Transfer to a serving dish. Dot with extra butter and bake in a preheated oven at 350°F (175°C) for 15-20 minutes if serving immediately.