Mash the berries well in a bowl until they form a puree. Transfer the raspberry puree to a small saucepan and add chia seeds along with your chosen sweetener. Turn the heat to low, stirring occasionally until the sauce becomes hot and starts to bubble gently.

While the raspberry mixture is heating, melt your chocolate using a double boiler or microwave method. Be careful not to overheat it; stirring frequently helps achieve a smooth consistency without burning.

Using mini cupcake liners or candy molds, spread about a teaspoon of melted chocolate up the sides of each liner. Then, scoop about two teaspoons of the raspberry filling into each cup before covering them with additional melted chocolate.

Place your filled cups in the refrigerator or freezer for several minutes until they set firmly. Alternatively, you can leave them on the counter for a couple of hours if you prefer a more gradual setting process.