Irresistible Raspberry Swirl Brioche

Ingredients

• 3 ¼ cups all-purpose flour
• 2 ¼ tsp active dry yeast (1 packet)
• ¼ cup granulated sugar
• ½ tsp salt
• ½ cup warm milk (about 110°F)
• 4 tbsp unsalted butter, softened
• 2 large eggs, at room temperature
• 1 tsp vanilla extract
• 1 tsp lemon zest (optional)
• 1 cup raspberry preserves or jam
• 1 tbsp cornstarch
• 2 tbsp water
• 1 tbsp butter, melted (for brushing)
• ¾ cup powdered sugar
• 1-2 tbsp lemon juice
• 1 tbsp milk or cream