Joy to the Food

0 Prepare: Separate the egg yolks from the egg whites. Store the egg whites in the fridge until ready to use. Pulverize or crush the graham crackers either with a food processor, a blender, or by putting them in a plastic bag and crushing them with a rolling pin. Preheat the oven to 350 degrees.Line an 8" x 8" pan with parchment paper so it hangs over the edges. See notes for baking in a different sized pan.
1 Make the crust: Mix the melted butter, graham crackers, and brown sugar until it resembles wet sand. Press this into your lined pan using your hand or a spatula. Bake this for 10 minutes
2 Make the custard: Whisk together all pumpkin pie filling ingredients until smooth. 
3 Combine: Remove the crust from the oven and pour the custard on top. Smooth out the top. Return to the oven to bake for another 30-35 minutes. When it's done, the top will be golden brown, stiff to the touch but will still have a slight wobble. Let it cool enough to handle and transfer to the fridge to cool completely (about 2 hours). 
4 Make the meringue: When the bars are almost cool (or when you want to serve them), make the meringue by whipping the egg whites and cream of tartar into soft peaks. You can do this with a whisk (or immersion blender with a whisk attachment), hand mixer, or in a stand mixer. Once soft peaks form (this can take upwards of 5-7 minutes depending on the method you use), add the powdered sugar 1/4th of a cup at the same time. Mix for 30 seconds to a minute each time after adding the sugar. Add in vanilla, cinnamon, or salt if desired. Keep mixing until the meringue becomes glossy. They do not need to be stiff peaks for these bars.
5 Combine: Top the bars with the meringue, slice, and enjoy! You can also slice the bars and then dollop the meringue on each bar. You can also toast the meringue using a torch or the broil setting on your oven. Or, you can just use coconut whipped cream.