Preheat the oven to 375°F / 190°C / gas mark 5.
Make the crust: In a dry frying pan over medium heat, toast the sunflower seeds until golden and fragrant, about 5 minutes. Remove the pan from the heat and pour the sunflower seeds into a food processor. Let cool for a few minutes, and then blend on high until the seeds resemble sand (do not over process, or you’ll end up with sunflower butter). Add the flour, salt, coconut oil, maple syrup, and iced water, and pulse until everything is well incorporated and the dough holds together.
Press the dough down very firmly onto the bottom and up the sides of a 7-inch / 18cm tart tin. Prick the crust all over with a fork, and bake for 15 to 25 minutes, until golden and crisp. Let cool completely.
Make the filling: Put the yogurt in a medium bowl. Slice the vanilla bean in half lengthwise, and scrape the seeds onto the yogurt. Add the maple syrup and fold to combine. Sweeten to taste with more maple syrup if desired.
Pour the yogurt mixture into the cooled tart shell. Arrange the quartered figs on top, drizzle with extra maple syrup if desired, and serve immediately.