Preheat oven to 350°F.
If you do not have a food processor, pull out your box grater. Grate the potatoes. They will brown quickly, so if you are doing by hand, as you grate the potatoes, put them in a bowl with water and and little bit of white vinegar (about a tablespoon).
When you are done grating the potatoes, grate the onion. You could also chop the onion very fine by hand.
Using your hands or a clean dish towel, wring out all the vinegar water from the potatoes. Add them to the large bowl with the grated onions.
Food processor:
First blend the onions with the regular blade until finely ground. Remove the onions and put in a large bowl.
Switch to the grating blade, grate the potatoes.
Add the potatoes to the bowl with the onions. Sprinkle on the corn starch. Add the salt and pepper.
Next, add on the eggs directly on top of the potato mixture. You could use your clean hands to mix it all together. Make sure the corn starch is completely combined with potatoes. You could also use forks or a wooden spoon to mix it all together, but by hand is easiest way.
If you’re using an oven safe casserole dish (I used a rectangular one), add the 4 tablespoons of oil and heat it up in the casserole for about 5 minutes.
If you’re using a 9 or 10-inch cast-iron skillet, add 4 tablespoons of the oil and heat on high heat for a few minutes (should take about 5 minutes to get it very hot). If you use a 9-inch skillet, the kugel will be taller.
Carefully add the potato mixture to the casserole (or your cast-iron skillet), taking care that it may splatter a little, as the oil is very hot. Spread out the potato mixture. You could twist the potatoes a little (if they’re long strands)and get a swirled texture look on top. Drizzle on the last tablespoon of oil.
Bake for about 60-70 minutes, or until kugel is golden brown on top and tender on the inside. The potatoes on top will be nice and crispy. You don’t want to over bake it. Mine was ready at about 65 minutes. If it’s browning too much on top, you could cover with foil paper for last few minutes of baking (I didn’t need to with mine).
Sprinkle on some chopped Italian parsley (optional). Cut into squares and pass around the table while it's warm.