In a 10" skillet, combine chopped apples, maple syrup, pumpkin pie spice, and salt. Cook over medium heat, stirring occasionally, until the apples start to soften, but are not mushy, 5 minutes. Then, add the cornstarch slurry, stirring quickly with a spatula. It should thicken the mixture in about 15 seconds.
2 Small Granny Smith Apples, peeled and chopped into ¼" cubes, ⅓ Cup Maple Syrup, 1 ¼ teaspoon Pumpkin Pie Spice, 1 pinch Kosher Salt