Preheat oven to 400°F (200°C).

Cut off the top 1/4 inch of the garlic head.

Drizzle the garlic head with olive oil and sprinkle with salt.

Wrap the garlic head in foil and roast for about 40 minutes, or until golden and caramelized.

Let the garlic cool until warm.

Peel the roasted garlic cloves.

In a food processor, chop 3 roasted garlic cloves.

Add pine nuts, Parmigiano-Reggiano, salt, and pepper; pulse to finely chop.

Add basil and pulse to finely chop.

With the motor running, add the remaining olive oil and blend to combine into a pesto.

Cook farfalle pasta in boiling salted water until al dente.

Reserve 3/4 cup of the pasta cooking water before draining the pasta.

Drain the pasta.

Toss the pasta with the pesto and about half of the reserved cooking water.

Add more pasta water for a looser consistency, if needed.

Halve the cherry tomatoes.

Toss the pasta with the cherry tomatoes and the remaining roasted garlic.

Season to taste with salt and pepper.

Serve immediately.