Here's a cake that is an autumn tradition in and around the Hill Country of Texas. Actually, I'm sure they got the idea from the apple orchards we have here in the canyon! Anyway, it is an absolutely delicious cake you can have for dessert or for breakfast. I have actually never made this in a 9x13 pan, but I imagine it would work if you don't have a cast iron pan to use.
Adjust an oven rack to the center position and preheat the oven to 350°(365º above 6,000 feet). Lightly grease a 12-inch cast-iron skillet or (if you must) a 9"x13"x2" pan.
In a medium bowl, whisk together the oil, apple sauce, melted butter, eggs, sugar, and vanilla. Peel, core and finely (≈3/8") chop the apples, stirring them in as you go. Stir in the pecans.
In a large mixing bowl, whisk together the flour, salt, baking soda, and cinnamon until everything is well combined. Make a "well" in center of these dry ingredients. Pour the wet ingredients into the well. Using a spatula or wooden spoon, fold the dry and wet ingredients together just until the flour is dampened. You will find this to be a very thick batter, In fact it’s more like a cookie batter. And while it may seem like there are way too many apple pieces, but it all works out in the end.
Turn the batter into your prepared skillet or baking pan, patting down the top so it’s even. Bake for 40-45 minutes until the top is lightly browned and an inserted knife comes out almost clean.
Let the cake cool in the pan on a cooling rack for 30 minutes before serving. Think seriously about serving this cake with a scoop of vanilla bean ice cream and/or cinnamon spiced whipped cream.