Turnip Green Tart

Name: Turnip Green Tart
Ingredients: 2 1/4 cups/9 oz/255 g all-purpose flour; 1 cup/4.5 oz/125 g spelt flour; scant 1 cup/4.5 oz medium coarse corn meal; 3/4 teaspoon fine grain salt; 1 1/4 cups/10 ounces/280 g unsalted butter, cut in cubes; 1 large egg yolk; 1/4 cup/60 ml - 3/4 cup/180 ml cold water; 1/4 lb./4 oz turnip greens, or spinach greens, de-stemmed; 1 small clove of garlic; 2 large eggs + 1 yolk; 3/4 cup veg. broth; 1/4 cup/60 ml heavy cream; scant 1/4 teaspoon salt (more if broth unsalted); 2 teaspoons Dijon-style mustard; 1 1/2 teaspoons herbs de Provence (opt.); gruyere cheese & a bit of crushed red pepper flakes, for topping