Mix together the yogurt and vanilla in a medium bowl until combined. Cover and refrigerate for at least 30 minutes to allow the flavors to meld.
Put the berries in a small saucepan, add 1/4 cup water, and simmer until just softened, about 5 minutes. Add granulated sugar to taste and stir in the lemon juice. Let cool slightly.
Divide the fruit among four 8-ounce ramekins and top with the granola. Fill the ramekins to the top with the yogurt (discard the vanilla bean if using). Cover and put in the freezer for 5 minutes.
Sprinkle 2 teaspoons of turbinado sugar over each ramekin. Caramelize the sugar with a blowtorch by slowly sweeping the flame back and forth. Let the sugar harden, about 2 minutes, before serving.
This recipe simply will not work under the broiler; the yogurt will melt. A small blowtorch (found at specialty kitchen stores or online) is essential.
Recipes reprinted from Brunch @ Bobby's by Bobby Flay. Published by Clarkson Potter Publishers.