Cream softened butter and granulated sugar in a large bowl until light and fluffy, about 2–3 minutes.
Add the egg and vanilla extract, mixing until smooth and well combined.
In a separate bowl, whisk together all-purpose flour, salt, and finely crushed freeze-dried raspberries.
Gradually add the dry ingredients to the wet mixture, stirring until a soft dough forms.
Wrap the dough in plastic wrap and refrigerate for 30 minutes to help maintain its shape.
Preheat the oven to 350°F (175°C).
Roll the chilled dough on a lightly floured surface to about 1/4-inch thickness.
Cut the dough into heart shapes and place them on a parchment-lined baking sheet.
Bake the cookies for 10–12 minutes or until the edges turn lightly golden.
Allow the cookies to cool completely before dipping.
Melt the dark chocolate and optional coconut oil in a microwave-safe bowl in 20-second intervals, stirring until smooth.
Dip half of each cooled cookie into the melted chocolate.
Place the dipped cookies on parchment paper and immediately sprinkle with crushed freeze-dried raspberries.
Let the chocolate set at room temperature or chill for 15–20 minutes until firm.