01 - Preheat oven to 450°F. Place butter in an 8x8-inch baking dish and melt in the oven while preheating for approximately 5 minutes.
02 - Remove dish from oven, swirl to coat bottom with melted butter. Stir in peach preserves until fully combined and set aside.
03 - In a large bowl, whisk together flour, baking powder, granulated sugar, and salt until evenly blended.
04 - Pour cold milk into dry ingredients. Gently mix until just combined, taking care not to overmix—the dough will be wet and shaggy.
05 - Pour biscuit dough directly over peach butter in the baking dish. Carefully spread dough evenly to all corners.
06 - Using a lightly greased knife or bench scraper, score dough into 9 squares in a 3x3 grid pattern to create clean separation lines.
07 - Bake for 22 to 25 minutes until tops are golden brown and center is completely set.
08 - While biscuits bake, whisk together powdered sugar, milk, and vanilla extract until smooth and pourable consistency is achieved.
09 - Remove biscuits from oven and let cool for 10 minutes. Drizzle vanilla glaze generously over warm biscuits before serving.