Nut buns

Ingredients

• 650 grams (5 1/4 cups) flour
• 1 tablespoon (0.5 ounces) cornstarch
• 1 teaspoon (0.35 ounces) baking powder
• 7 grams (2 1/4 teaspoons) dry yeast
• 300 milliliters (1 1/4 cups) milk
• 2 eggs
• 1 tablespoon (0.5 ounces) sour cream
• 50 grams (1/4 cup) sugar
• 50 grams (1/4 cup) butter at room temperature
• Pinch of salt
• 100 grams (1 cup) chopped nuts
• 100 grams (1/2 cup) cane sugar
• 1 egg