Prepare the Blueberry Filling:

• In a medium saucepan over medium heat, combine the blueberries, granulated sugar, lemon juice, and 2 tablespoons of water. Cook until the blueberries release their juices and the mixture begins to simmer.
• In a small bowl, mix the cornstarch with the remaining tablespoon of water until smooth. Stir this slurry into the blueberry mixture.
• Continue cooking, stirring constantly, until the mixture thickens, approximately 1–2 minutes. Remove from heat and let it cool completely.

Prepare the Cream Cheese Filling:

• In a medium bowl, beat the softened cream cheese, granulated sugar, and vanilla extract until smooth and creamy.

Assemble the Egg Rolls:

• Lay an egg roll wrapper on a clean, dry surface with one corner pointing toward you, forming a diamond shape.
• Spread about 1 tablespoon of the cream cheese mixture horizontally across the center of the wrapper, leaving space at the edges.
• Top the cream cheese with 1 tablespoon of the cooled blueberry filling.
• Fold the bottom corner over the filling, then fold in the side corners, and roll up tightly toward the top corner. Brush a small amount of the beaten egg on the top corner to seal the egg roll.
• Repeat this process with the remaining wrappers and filling.

Fry the Egg Rolls:

• In a large, deep skillet or saucepan, heat about 2 inches of vegetable oil to 350°F (175°C).
• Carefully place a few egg rolls into the hot oil, ensuring not to overcrowd the pan. Fry each side until golden brown, approximately 2–3 minutes per side.
• Remove the egg rolls from the oil and drain on a plate lined with paper towels.

Serve:

• Once slightly cooled, dust the egg rolls with powdered sugar.
• Serve warm, optionally with a side of vanilla ice cream or a drizzle of chocolate sauce.