01 - In a medium bowl, beat cream cheese, sugar, vanilla extract, and sour cream until completely smooth and creamy, ensuring no lumps remain.
02 - Lay out tortillas on a clean surface. Spoon approximately 2 tablespoons of cheesecake filling onto the lower third of each tortilla. Add 1 tablespoon of diced berries if desired. Fold in the sides and roll tightly from bottom to top, forming a secure burrito shape. Secure with toothpicks if necessary to prevent unrolling during frying.
03 - Pour vegetable oil into a deep skillet or saucepan to a depth of 2 inches. Heat to 350°F, maintaining temperature throughout the frying process.
04 - Carefully place chimichangas in hot oil, seam side down, working in batches to avoid overcrowding. Fry for 2 to 3 minutes per side until golden brown and crispy. Remove using a slotted spoon and transfer to paper towels to drain excess oil.
05 - While chimichangas are still warm, brush each one generously with melted butter to help the cinnamon sugar coating adhere.
06 - Combine granulated sugar and ground cinnamon in a shallow dish, mixing thoroughly. Roll warm, buttered chimichangas in the mixture, pressing gently to ensure even coating on all sides.
07 - Serve immediately while warm and crispy. Garnish with whipped cream, additional fresh berries, or chocolate sauce if desired.