Step 1: Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Step 2: In a mixing bowl, combine the flour, baking powder, and salt. Mix well.
Step 3: Add the Greek yogurt and milk to the dry ingredients. Stir until a dough forms. If the dough is too sticky, add a little more flour as needed.
Step 4: Turn the dough out onto a lightly floured surface and knead gently for about 1 minute until smooth.
Step 5: Divide the dough into 8 equal pieces. Roll each piece into a long rope, about 8 inches long.
Step 6: Tie each rope into a knot, tucking the ends underneath. Place the knots on the prepared baking sheet.
Step 7: In a small bowl, mix the melted butter, minced garlic, parsley, red pepper flakes, and salt until well combined.
Step 8: Brush each knot generously with the garlic butter mixture, reserving some for later.
Step 9: Bake in the preheated oven for 15-20 minutes, or until the knots are golden brown.
Step 10: Remove from the oven and immediately brush with the remaining garlic butter. Sprinkle with grated Parmesan cheese if desired.
Step 11: Serve warm with marinara sauce for dipping or enjoy them on their own!