Roll out the puff pastry to 1/4 inch thick on a floured surface. Transfer the pastry to a 9-inch cast-iron skillet and gently press it into the skillet, allowing the extra to hang over the edges. Brush the pastry with the apricot jam.
Place the blueberries, blackberries, strawberries, sugar, cornstarch and lemon juice in a bowl. Toss to combine, then transfer the mixture to the prepared skillet.
Bake until the pastry is golden and the fruit is bubbling, 30 to 35 minutes. If the edges begin to get too dark, lightly cover with foil.
Top with the granola and spoonfuls of yogurt. Garnish with mint and the extra berries. Drizzle with the honey, slice and enjoy.