Crema catalana is a classic Spanish dessert similar to the French crème brûlée. Here, the basic recipe gets a twist with the addition of chocolate and fresh berries. Note that you will need a culinary or crème brûlée torch to caramelize the sugared top of the custard. You can make the vanilla syrup up to two weeks in advance, but hold off macerating (soaking) the fruit until no more than 15 minutes before you are going to serve the custards. The custards need to chill for about four hours, but once caramelized, they shouldn't sit more than about 10 minutes: You want the tops brittle and the creamy custard beneath cold.
Combine the vanilla bean in a saucepan with the water and granulated sugar. Bring to a boil, then reduce the heat and simmer for 15 minutes. Remove from the heat and let cool to room temperature. (It will keep in an airtight container in the refrigerator for up to 2 weeks.)
Combine the milk and gelatin and let sit until the gelatin is completely dissolved, for 10 minutes. Set a double-boiler over medium heat with 2-inches water in the bottom and bring to a boil. Decrease the heat to low, place the chocolate in the top of the double-boiler, and stir to melt the chocolate, taking care not to let it scorch.
Combine the cream and sugar in a saucepan and bring to a simmer over low heat, stirring occasionally, 3-5 minutes. Put the egg yolks in a large heatproof bowl. Pour half of the hot cream mixture in a steady stream into the egg yolks, stirring constantly.
Add the tempered yolks back to the cream mixture in the saucepan and cook over low heat, stirring constantly, until the custard thickens to the point of coating the back of a spoon. Remove the custard from the heat. Add the gelatin mixture and melted chocolate and mix well to incorporate them. Stir in the salt.
Strain the custard through a fine-meshed sieve and pour it into 8 shallow 6-ounce custard cups. Let cool to room temperature. Refrigerate for at least 4 hours or up to 3 days, covered tightly with plastic wrap to keep the tops from drying out and to prevent refrigerator smells from permeating the custards.
When you are ready to serve the custards, macerate the fruit: Combine the berries in a bowl with ½ cup vanilla simple syrup; they can be left to soak at room temperature for up to 15 minutes. Reserve the remaining syrup for another use.
To caramelize the chilled custards, just before serving, coat the tops with raw sugar, gently tipping off any excess: It should be a fine, thin layer of sugar. Use a culinary or crème brûlée torch to caramelize the sugar evenly across the top of each custard. This should take about 1 minute per custard, but may happen more quickly: Be watchful and use caution. Garnish the custards with berries and lemon zest and serve immediately.