1. Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or a silicone baking mat for easy cleanup.
2. In a medium bowl, combine the softened cream cheese, sugar, vanilla extract, and lemon juice. Mix until smooth and creamy. I like to use a hand mixer for this step, but a sturdy spoon and some elbow grease work just fine.
3. Gently fold the blueberries into the cream cheese mixture. If you’re worried about the filling becoming too watery, toss the blueberries with a little cornstarch before folding them in.
4. Lay out one egg roll wrapper on a clean, dry surface with one corner pointing toward you (like a diamond shape). Spoon about 2 tablespoons of the filling near the corner closest to you.
5. Fold that corner over the filling, then fold in the two side corners snugly around the filling. Roll the wrapper tightly toward the opposite corner.
6. Use the cornstarch and water mixture as glue to seal the final corner. This little trick ensures your egg rolls don’t open up during baking—something I learned the hard way early on, after finding one egg roll mysteriously emptied on the baking tray!
7. Place the sealed egg rolls seam side down on your prepared baking sheet. Lightly brush or spray the tops with cooking spray or melted butter to encourage browning.
8. Bake for 12-15 minutes, turning halfway through, until the egg rolls are golden brown and crispy. The aroma of baked fruit and cream cheese filling wafting through your kitchen will be your cue that they’re done.

From experience, I recommend watching closely after the 10-minute mark to avoid over-browning, especially if your oven runs hot. These cook quickly, and the goal is a crisp exterior with a melty, luscious filling inside.