1. In a food processor, finely chop the garlic. Add basil leaves and chop until fine. Add the cheese, nuts, salt, and pepper; pulse until the consistency of a coarse paste.
2. With the food processor running, slowly pour olive oil through the feed tube and continue mixing until the oil is completely combined with paste.
3. Place baguette slices in a single layer on a baking sheet. Toast under oven broiler until lightly browned; flip them over and toast the other side.
4. Spread the tops with pesto, then sprinkle with grated cheese. Return to oven and broil until cheese has melted.