Preheat your oven to 375°F (190°C). Grease a 9x9 inch baking dish or a similar 2-quart baking dish with butter or non-stick spray.

In a large bowl, combine the sliced apples and lemon juice, tossing gently to prevent browning.

In a separate small bowl, whisk together the light brown sugar, 2 tbsp of all-purpose flour, 1 tsp of ground cinnamon, and the ground nutmeg.

Pour the sugar-flour mixture and the 2 tbsp of melted butter over the apples. Toss everything together until the apple slices are evenly coated.

Spread the apple filling in an even layer in the bottom of your prepared baking dish.

In a medium bowl, whisk together the 1 1/2 cups of all-purpose flour, cream of tartar, baking soda, and salt. Set aside.

In a separate large bowl, using an electric mixer or a stand mixer with the paddle attachment, cream together the 1/2 cup of softened butter and 3/4 cup of granulated sugar on medium-high speed until light and fluffy, about 2-3 minutes.

Add the egg and vanilla extract to the butter mixture and beat until well combined, scraping down the sides of the bowl as needed.

With the mixer on low speed, gradually add the dry flour mixture to the wet ingredients. Mix until just combined. Be careful not to overmix; the dough will be soft.

In a small bowl, mix together the 2 tbsp of granulated sugar and 2 tsp of ground cinnamon for the dusting.

Drop rounded tablespoonfuls of the snickerdoodle dough evenly over the apple filling. It doesn't need to cover the entire surface, as it will spread while baking.

Sprinkle the cinnamon-sugar mixture generously and evenly over the top of the dough.

Bake for 35-40 minutes, or until the fruit filling is bubbly and thick, and the snickerdoodle topping is golden brown and cooked through. A toothpick inserted into the center of the topping should come out with moist crumbs.

Remove the cobbler from the oven and let it cool on a wire rack for at least 15-20 minutes before serving. This allows the filling to set and makes it easier to serve.