01 - Preheat oven to 450°F. Place butter in an 8x8-inch baking dish and put in oven to melt while preheating, approximately 5 minutes.
02 - Remove dish from oven, swirl to coat bottom evenly. Stir peach preserves into melted butter until well combined. Set aside.
03 - In large bowl, whisk together flour, baking powder, sugar, and salt until uniformly blended.
04 - Pour cold milk into flour mixture. Gently mix until just combined. Do not overmix; batter will remain wet and slightly shaggy.
05 - Pour biscuit dough over peach butter in baking dish. Carefully spread evenly to corners. Using lightly greased knife or bench scraper, score dough into 9 squares in a 3x3 grid.
06 - Bake for 22 to 25 minutes until top is golden brown and center is set.
07 - While biscuits bake, whisk together powdered sugar, milk, and vanilla extract until smooth and pourable consistency is achieved.
08 - Remove biscuits from oven and cool for 10 minutes. Drizzle vanilla glaze generously over warm biscuits before serving.