Line a baking sheet with parchment paper. Spray with nonstick cooking spray or melted butter.
In a large bowl, combine warm water and yeast. Let sit for 5 minutes until frothy. Add butter, sugar and egg to the yeasted mixture. Stir in the flour, baking powder and salt with a wooden spoon just until combined. Shape into a ball. Cover with a towel. Let rise in a warm place for 30 minutes.
Divide dough in half. Roll each half on a floured surface in a circle about 12 inches in diameter. Cut into 12 equal triangles. Starting with the wider end, roll up each dough triangle. Place on prepared baking sheet. Cover baking pan with a clean, dry towel and let dough rise for 20-30 minutes.
Preheat oven to 375 degrees F. Bake rolls until golden brown, 15-20 minutes. Remove from oven. Immediately brush with butter.
Store in an airtight container for up to 3 days.