Heat oven to 400F degrees.

Cut 1/4 to 1/2 inch from the top of the garlic heads, exposing the cloves. Transfer the heads to a baking pan, cut side up, and drizzle with olive oil, salt and pepper.

Wrap the heads with aluminum foil and roast for about 1 hour or until the cloves are soft and fragrant, almost caramelized on top.

Remove from the oven - leave the oven on! - and allow them to cool enough to handle. Then, using your fingers (or a fork), squeeze the garlic out into a small bowl. Using a fork, mash the roasted garlic cloves until smooth and resembling a paste.

Transfer this garlic paste to a big bowl and add the ricotta, 2/3 of the parmesan, the egg, thyme, salt and pepper. Mix well, with a spoon or whisk, until combined.

Transfer the mixture to a 2-cup baking dish brushed with olive oil. Sprinkle the remaining parmesan and bake until golden and puffed, 25 to 30 minutes.

Serve immediately with crostini or crusty bread. You can garnish with some thyme sprigs or serve as is!