Preheat your oven to 375°F (190°C) and line a large baking sheet with parchment paper. Make sure the parchment lies flat so the cheese melts evenly and doesn’t spread unevenly.
In a medium mixing bowl, add the cooked chicken, Greek yogurt, minced garlic, green onion, salt, black pepper, and paprika. Stir gently until the chicken is evenly coated and the mixture looks creamy but not wet. If it feels too thick, add 1 teaspoon of yogurt; if too loose, mix in a little more chicken.
Place the mozzarella slices flat on the prepared baking sheet, leaving a small gap between each slice so they soften evenly without merging together.
Transfer the baking sheet to the oven and bake for 4–6 minutes, just until the cheese melts and becomes soft and flexible. Do not let it brown or bubble aggressively, as overbaked cheese will release oil and tear when rolled.
Remove the baking sheet from the oven and let the cheese rest for about 30 seconds. This short rest makes the slices easier to handle while keeping them pliable.
Spoon the chicken mixture along one long edge of each softened cheese slice, keeping the filling compact and evenly distributed. Avoid overfilling, as too much filling can cause the cheese to split.
Starting from the filled edge, carefully roll the cheese around the chicken into a tight roll-up. Place each roll seam-side down on the baking sheet so it holds its shape during the final bake.
Return the baking sheet to the oven and bake for 6–8 minutes, or until the roll-ups are set, lightly golden, and holding together without spreading.
Remove from the oven and allow the roll-ups to rest for 2–3 minutes before serving. This helps the cheese firm slightly and improves texture. Serve warm, or let cool completely and store in airtight containers for meal prep.