In a mixing bowl, combine creamy peanut butter and honey until blended smooth. Add a pinch of sea salt and fold in the crushed granola until evenly coated.

In a separate bowl, whisk the Greek yogurt until creamy. Add vanilla extract if using and mix well until smooth.

Line a muffin tin with cupcake liners. Spoon the granola mixture into each liner, pressing down firmly.

Spoon the yogurt mixture over the granola base, filling each liner about three-quarters full.

Sprinkle fresh berries and finely chopped walnuts on top, then drizzle a dash of honey over the berries.

Transfer the muffin tin into the freezer and chill for 30 to 60 minutes, or until completely frozen.

Remove the muffin tin from the freezer and let the bites sit at room temperature for 2-3 minutes before gently peeling away the liners.