Blue Raspberry Laminated Brioche Buns

Ingredients

• 1/3 cup whole milk (110-115°F)
• 1 (0.25oz) package (7g) or 2 1/4 teaspoons Platinum Yeast
• 2 1/2 tablespoons granulated sugar
• 1/3 cup bread flour
• 3 cups bread flour
• 1 1/2 teaspoons table salt
• 4 large eggs
• 6 ounces (1 1/2 sticks) cold unsalted butter
• 1 pound (4 sticks) cold unsalted butter (cut into thin slices)
• 3/4 cup granulated sugar
• Zest of 1 lemon
• 1 cup fresh blueberries
• 2 tablespoons unsalted butter (melted)
• 1 large egg
• 1 egg yolk
• 2 cups powdered sugar
• 1/2 cup raspberry jam
• 1/4 cup milk (with more to thin if needed)