The Best Swirled Blackberry-Lavender Sheet Cake Recipe Ever Made - The Dream Cafe

Ingredients

• 6 cups (1.4 kg) fresh or frozen blackberries
• 1-2 tablespoons (4-8 g) dried lavender
• 1 tablespoon (15 ml) lemon juice
• 1 tablespoon (15 ml) vanilla extract
• 3 cups (375 g) all-purpose flour
• 1 ½ cups (300 g) granulated sugar
• 1 ½ cups (180 g) powdered sugar
• 1 teaspoon (6 g) kosher salt
• ½ teaspoon (2.5 g) baking soda
• 1 ½ teaspoons (7.5 g) baking powder
• 3 large eggs
• 1 cup (240 ml) milk
• 1 cup (240 ml) melted coconut oil
• ½ cup (120 ml) sour cream
• 16 tablespoons (226 g) salted butter, at room temperature
• ½ cup (170 g) honey
• 6 ounces (170 g) white chocolate, melted and cooled