Low FODMAP Chocolate Raspberry Bûche de Noël

Ingredients

• 3 cups (720 ml) heavy cream, (lactose-free if you like)
• 12 ounces (340 g) dark chocolate, (about 66% cacao mass, such as Guittard, finely chopped)
• 6 ounces (170 g) raspberries
• 1 ¼ cups (181 g) low FODMAP gluten-free flour,
• ¾ cup (149 g) sugar, (divided)
• 1 ½ teaspoon baking powder; (use gluten-free if following a gluten-free diet)
• ¼ teaspoon salt
• 5 large eggs, (at room temperature, separated)
• ½ cup (120 ml) neutral flavored vegetable oil such as rice bran or canola
• ¼ cup (60 ml) water, (at room temperature)
• 2 teaspoons vanilla extract
• ¼ teaspoon cream of tartar
• 16 ounces (455 g) dark chocolate, (about 66% cacao mass, such as Guittard, finely chopped)
• 1 ½ cups (360 ml) heavy cream, (lactose-free if you like)
• 6 tablespoons (85 g) unsalted butter, (at room temperature, cut into pieces)