Preheat a convection oven to 190°C (375°F) and line a standard 12-cup muffin tin with paper liners.
In a large mixing bowl, sift together flour, granulated sugar, brown sugar, baking powder, baking soda, and salt.
In a separate vessel, whisk together the milk, melted butter, egg, and vanilla extract until emulsified.
Gently fold the wet ingredients into the dry ingredients using a spatula until just combined; do not overmix.
Fold in the chocolate chips until evenly distributed through the batter.
Dispense 1.5 tablespoons of batter into the bottom of each muffin liner.
Deposit 2 teaspoons (approximately 10g) of hazelnut spread into the center of each batter-filled liner.
Top each muffin with the remaining batter, ensuring the hazelnut center is fully enclosed.
Bake for 18 to 20 minutes, or until the internal temperature reaches 95°C (203°F) and the tops are golden brown.
Allow muffins to rest in the tin for 5 minutes before transferring to a wire rack for final cooling.