Yes, you can use another spread of your choice for the molten center of the madeleines. Just make sure it has a similar consistency to Nutella.

No, it is not necessary to refrigerate the spread before using it. It will be easier to handle at room temperature.

Generally, 10 to 12 minutes of baking at the recommended temperature should be enough to achieve a perfect molten Nutella center. Monitor the baking carefully to avoid overcooking the madeleines.

To prevent the molten center from overflowing, make sure to seal the Nutella inside each madeleine by completely covering it with batter. Gently press to seal it well.

Yes, you can freeze the madeleines once they are completely cooled. Place them in an airtight freezer bag and store them in the freezer for up to 3 months. To enjoy them, let them thaw at room temperature for a few hours.

To achieve a beautiful hump on top of the madeleines, it is important to let the batter rest in the refrigerator before baking. Also, preheat your oven to a high temperature and place the molds in the center of the oven.

If you are using non-stick silicone molds, it is not necessary to butter and flour them. However, if you are using metal molds, it is preferable to butter and flour them to facilitate unmolding.

Yes, you can add chocolate chips to the madeleine batter for an additional touch of indulgence. Gently fold them into the batter before filling the molds.

The madeleines can be stored in an airtight container at room temperature for 2 to 3 days. However, they are best enjoyed fresh, especially to savor the molten center.

Yes, you can use another madeleine batter recipe of your choice and follow the method of adding the Nutella spread in the center. Just make sure to adjust the baking times accordingly.