1. Prepare the Puff Pastry

Start by preheating your oven to 425°F (218°C). If you’re using frozen puff pastry, make sure to thaw it according to the instructions on the packaging. The dough should be pliable but still cool to the touch, which will make it easier to handle. Refrigerated puff pastry is generally ready to use immediately, so you can skip the thawing step if you’re using this version. Using a rolling pin, gently flatten the pastry sheets to about 1/8-inch thickness. This step helps to ensure that the layers of puff pastry bake evenly. Be careful not to roll it out too thin. Next, cut each sheet of puff pastry into four equal squares, resulting in 8 squares in total. Each square should be about 5 inches on all sides, but feel free to adjust the size to your liking. If you cut smaller squares, keep in mind that the baking time may vary, so be sure to check your croissants closely as they bake.

2. Form the Croissants

Now it’s time to shape your croissants! Begin by brushing each puff pastry square with a thin layer of egg wash. The egg wash is a mixture of beaten egg and water that helps give the croissants their golden, shiny appearance when baked. Take one corner of each square and fold it towards the opposite corner, creating a triangle shape. Carefully press the edges together to seal the croissant, making sure the seam is tightly pressed to avoid any leaks during baking. Once all the croissants are folded, brush the tops of each one with more egg wash. For an extra touch of sweetness and crunch, sprinkle them with coarse sugar. This step is optional, but it gives the croissants a lovely texture and a slightly sweet finish.

3. Bake the Croissants

Place the croissants on a baking sheet lined with parchment paper or a silicone baking mat for easy cleanup. Bake the croissants in your preheated oven for 22 to 25 minutes, or until they are deep golden brown. Be sure to check them around the 20-minute mark, as baking times may vary depending on the thickness of the pastry and your oven’s temperature. If you’re using refrigerated puff pastry, the croissants may bake a few minutes faster, so monitor them closely to prevent burning. When they’re done, the croissants should be puffed up, golden, and crisp. Let them cool completely before cutting into them. The pastry layers need to set before you add the filling to ensure they maintain their structure.

4. Make the Homemade Berry Jam

While the croissants are baking, take the time to prepare the berry jam. In a medium-sized saucepan, combine frozen wild blueberries, granulated sugar, and lemon juice. Set the pot over medium heat and bring the mixture to a simmer. Stir frequently to ensure that the sugar dissolves evenly. Allow the jam to cook for 15 to 20 minutes, stirring occasionally. The berries will break down, and the sauce will thicken. Keep a close eye on the jam to prevent burning. If you’re using fresh fruit, it might take an additional 5 minutes to cook, as fresh berries have more water content than frozen berries. Once the jam has thickened to your desired consistency, remove it from the heat and set it aside to cool. It will continue to thicken as it cools.

5. Prepare the Cream Filling

Next, it’s time to make the cream filling. Begin by placing the cold heavy whipping cream, powdered sugar, and vanilla extract in a large mixing bowl. Using an electric hand mixer, beat the mixture until stiff peaks form. This will create a thick, creamy whipped cream base. In a separate bowl, beat the cream cheese and sour cream for 1 to 2 minutes, until the mixture becomes smooth and fluffy. Once the cream cheese and sour cream are fully combined, gently fold in the whipped cream mixture, one-third at a time. Continue folding until the cream is fully combined, ensuring that the mixture remains light and airy. Taste the cream filling and adjust the sweetness to your liking. If you prefer a sweeter filling, feel free to add a little more powdered sugar until it reaches your desired level of sweetness.

6. Assemble the Croissants

Once the croissants are completely cooled, it’s time to assemble your Berries and Cream Filled Croissants! Use a serrated knife to gently cut a slit into the side of each croissant. Be careful not to cut all the way through; you want to create a pocket that you can fill with the delicious jam and cream. Spoon a small amount of the homemade berry jam into each croissant, then top it with a generous dollop of the cream filling. Be mindful not to overfill the croissants, as this can cause the pastry to tear or make the filling too messy. Just a spoonful of each is all you need. For a finishing touch, dust the croissants with a light sprinkling of powdered sugar to make them look extra special.