In a large mixing bowl, combine crispy Fruity Pebbles cereal with melted unsalted butter, mixing well until all pieces are evenly coated. Pour the mixture into taco-shaped molds, pressing firmly to form the shape. Refrigerate for at least 30 minutes to set.

While the taco shells chill, prepare the creamy filling. Beat softened cream cheese using a hand mixer until light and fluffy, then gradually add in sifted powdered sugar and vanilla extract, mixing until smooth.

Gently fold in whipped cream using a spatula, being careful to preserve the volume. The filling should become fluffy and thicker.

Retrieve taco shells from the refrigerator and fill each with the cheesecake mixture, heaping it slightly for an enticing presentation.

Sprinkle additional Fruity Pebbles on top of each taco before serving. Serve immediately or refrigerate for another 30 minutes for a firmer filling.