For the chutney: In a saucepan over medium heat, sweat the onions until softened, about 4 minutes. Add the green apples and reduce the heat to low and cook until the apples soften, about 5 minutes. Add the gari, sugar, cumin, and salt and pepper to taste. Once completely softened, it only takes a couple minutes, puree everything in a food processor. Set aside to cool. Once the mixture is cooled, add equal parts yogurt and puree again. The chutney can be refrigerated for up to 4 days.
For the samosas: In a preheated saucepan over medium-high heat, add a little bit of vegetable oil and brown the chicken with the onions, garlic puree, cumin and chili flakes, about 15 minutes. The chicken will render liquid as will the onions. Once browned and fully cooked through, season with salt and pepper. Set aside to cool. Then, add the Asiago and sage. Set aside. Cut the spring roll wrappers in half, creating two long, rectangle-shaped strips. Using a pastry brush, place egg wash on the top half of the strip. Add about 1 tablespoon of the chicken filling to the bottom half of the strip (the half that does not have the egg wash). Starting at the bottom, fold the wrapper at a 45-degree angle, making triangles over and over as you work your way up, similar to folding spanakopita. Apply egg wash if needed to seal the edges once you are done folding the wrapper. Heat a deep pot with oil to 350 degrees F. Deep-fry the samosas until lightly browned and crispy, 3 to 4 minutes. Then drain on paper towels and season with salt and pepper while the samosas are still hot and wet. Serve the apple cumin chutney on the side with the samosas.