Buttery Soft Pretzels

Bahan-bahan (12 porsi)

• 1 1/2 cups warm (110 to 115°F) milk or water
• 1 tablespoon brown sugar
• 1 (0.25-ounce) package active dry yeast
• 4 1/2 cups all-purpose flour, plus more if needed
• 2 tablespoons melted butter, plus extra for brushing
• 1 teaspoon fine sea salt
• 9 cups water
• 1/3 cup baking soda
• 1 large egg (whisked with 1 tablespoon water)
• pretzel salt or coarse sea salt, for sprinkling