1 tablespoon plus 2 teaspoons powdered unflavored gelatin
2 cups whole milk
1 cup sugar
1 vanilla bean, split and seeds scraped away, or ¼ teaspoon vanilla extract
2 cups very cold heavy cream
1 tablespoon unsalted butter, at room temperature
¼ cup sugar
2 tablespoons light corn syrup
¼ cup fennel seeds
¼ teaspoon baking soda
Fresh seasonal berries, for serving
Put ¼ cup cold water in a small bowl. Sprinkle the gelatin over it and let it soak for 5 minutes, or until softened.
Combine the milk, sugar, and vanilla bean halves in a large saucepan.
Stir over medium-high heat until the sugar has dissolved, then bring to a gentle boil.
Remove from the heat and let cool for 2 minutes.
Stir in the gelatin mixture until dissolved.
Stir in the cream and remove the pieces of vanilla bean.
Cool to room temperature, then refrigerate for 30 minutes, or until the mixture begins to thicken.
Pour ½ cup of the mixture into each of eight 6-ounce ramekins or glasses.
Refrigerate for at least 2 hours, until set (if you plan to refrigerate overnight, cover each with plastic wrap).
Line a baking sheet with foil and rub with the butter.
Combine the sugar, corn syrup, and 2 tablespoons of water in a small, heavy saucepan.
Heat over medium-high heat, stirring, until the sugar has dissolved. Then, bring to a boil and simmer until the bubbles begin to break much more slowly (Note: Molten sugar is extremely hot; handle it with care.
Shortly after that, the mixture will start to brown. Caramelize it to a light amber color- not dark brown.
Remove from the heat and stir in the fennel seeds and baking soda (the mixture will bubble up slowly and expand like a science experiment).
Scoop it out onto the buttered foil with a spatula and spread thinly; it will continue bubbling for a few seconds.
Cool completely, then chop the hard brittle into small, rough pieces.
To serve, top each panna cotta with a few berries and scatter with the chopped brittle.