Place the potatoes in a large saucepan and pour over enough cold water to cover.

Set the pan over high heat and bring to a boil. Boil for 12 to 15 minutes, until the potatoes are fork tender.

Drain and, when cool enough to handle, remove the potato skin.

Press the potatoes through a potato ricer or fine sieve. Set aside.

On a large, clean surface, combine the flour and salt and mix with your fingers to combine.

Make a well in the center of the flour mixture and add the egg and riced potatoes to the well.

Using your hands, mix the flour, potatoes, and egg together until you have a soft dough. The dough should not be sticky; if it is, add a small amount of flour.

Working on a lightly floured surface, shape the dough into 5 to 6 ropes, each about ½-inch thick. Cut the ropes crosswise into ¾-inch-long pieces.

Gently roll the pieces over the back of a fork to create tine marks.

Transfer the gnocchi to a parchment paper-lined baking sheet, in a single layer without touching, and let stand for 30 minutes.

Meanwhile, to make the tomato sauce, heat the oil in a large saucepan over medium heat.

Add the garlic, Italian seasoning, basil, and red pepper flakes and cook for 30 seconds.

Add the tomatoes with the liquid from the can and bring to a simmer.

Reduce the heat to medium-low and simmer for 15 minutes.

Using a potato masher or fork, smash the tomatoes to create a thick, chunky sauce.

Season the sauce with salt and pepper.

To cook the gnocchi, bring a large pot of salted water to a boil.

Add the gnocchi and cook until they float to the top, about 1 to 3 minutes.

As soon as the gnocchi float, use a slotted spoon or fine mesh strainer to transfer them to the sauce.

Cook for 1 minute to heat through.

Top the gnocchi with fresh basil and serve with parmesan cheese on the side.