Peel and grate potatoes using the largest holes of a box grater. After grating, rinse the potatoes with cold water to remove excess starch. Also peel and grate the apples and add them to your potato pile. Squeeze with a towel to remove extra moisture and transfer to a large bowl.
Peel your onions, then grate them into the bowl with the potatoes and apples. Use a finer grate for the onions. I add mine super finely shredded - essentially as an onion paste.
Add the eggs, salt, pepper, flour, paprika and cinnamon to the mix. Stir together. You want a wet mix, but not too liquidy. If things start to look soupy, add a bit more flour (one tablespoon at a time).
Heat 1/2 cup of oil in a large pan over medium-high heat. Add a quarter cup of latke mix at a time and let each latke fry for about four minutes on each side. You want a nice, light brown color. Be sure not to crowd the pan - you should be able to fit 2-4 in at once, but will definitely need to do a few different batches. If your first couple of batches have trouble sticking together, add another egg to the mix, which should help bind them. You'll also probably need to add more oil to the pan to get through all your latke mix. Don't worry - that's totally normal.
Once each latke is done, transfer it to a paper town lined plate to sop up the excess oil.
Now whisk together the liquid smoke, sour cream, and smoky sea salt.
Now time to eat! Add a dollop of smoky sour cream to each plate of latkes. If you want a bit of extra apple-y flavor, grate some apple on top.