Step 1: Preheat the Oven: Begin by preheating your oven to 350°F (175°C). Line your muffin tin with parchment paper liners.
Step 2: Mix the Wet Ingredients: In a large mixing bowl, combine the melted salted butter, maple syrup, and vanilla extract. Add the eggs, Greek yogurt, and milk. Mix until smooth.
Step 3: Combine the Dry Ingredients: In a separate bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt.
Step 4: Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet mixture. Stir gently until just combined.
Step 5: Add the Chocolate Chips: Toss the chocolate chips in a tablespoon of flour and fold into the batter.
Step 6: Fill the Muffin Tin: Scoop the batter into the prepared muffin tin, filling each cup about 3/4 full.
Step 7: Prepare the Topping: Mix the melted butter with the apple butter and drizzle over the muffin batter.
Step 8: Bake: Bake for 18-22 minutes, or until a toothpick comes out clean.
Step 9: Cool and Enjoy: Let the muffins cool in the tin for 5 minutes, then transfer to a cooling rack.