To prepare the potatoes, wash them and, using a paring knife or fork, prick the skin a few times. Place the potatoes on a microwave-safe plate and microwave on high for 6 minutes. Flip the potatoes and microwave until fully cooked through, about another 5 to 6 minutes. If the potatoes are still undercooked, microwave in 1-minute increments until they are cooked. Alternatively, the potatoes can be baked in a 400°F oven until tender and cooked through, about 50 to 70 minutes. Let cool until warm to the touch, about 10 minutes.

While the potatoes are cooling, bring a large pot of salted water to a boil. Add the spinach and cook until wilted and tender, about 3 to 4 minutes. Using tongs or a slotted spoon, remove the spinach and place in a colander. Reduce the heat under the water to medium low and keep warm (you will use this to cook the gnocchi later).

Squeeze out the excess water from the spinach and place it in a blender with the egg, egg yolk, nutmeg, white pepper, and 1¼ teaspoons salt. Blend until smooth and transfer into a large bowl.

When the potatoes are cool enough to handle, gently peel each potato. Using a ricer, rice the cooked potatoes into the spinach-egg mixture. If you don’t have a ricer, you can also grate the potatoes on the large side of a grater. Add the parmesan cheese and mix well. Sprinkle 1 cup flour over the potato and egg mixture and, using your hands knead everything together in the bowl (making sure not to over-knead, which will start to develop the gluten in the flour).

Pinch a small piece of dough off and roll it into a ball. Bring the water back to a simmer, drop the tester ball into the water, and cook until it floats to the surface, about 1 minute. Remove with a slotted spoon and let cool for 1 minute before tasting. If the gnocchi tastes a little too soft or if it starts to fall apart in the water, add more flour 2 tablespoons at a time. If it holds together and is pillowy but not mushy, you are ready to start rolling the gnocchi!

Turn the dough out onto a generously floured surface and divide into four portions. Taking one portion, roll into a long rope, about a half inch in diameter. Cut the gnocchi with a lightly floured knife or pastry scraper into 3/4-inch pieces. Transfer the finished uncooked gnocchi to a lightly floured baking sheet. Repeat with the remaining dough. If you want you can take each gnocchi and roll it down the tines of a floured fork to create more texture on the outside of the dumpling.

Bring the water back up to a gentle boil, then add the gnocchi and simmer until the gnocchi are cooked through and start to float, about 1 to 1½ minutes. Remove with a slotted spoon and transfer to a plate.

While the gnocchi are cooking, heat the olive oil in a large skillet over medium high heat. Fry the sage leaves until bright green and crisp, about 15 to 30 seconds, remove with a slotted spoon, and transfer to a paper towel-lined plate. Add the cooked gnocchi to the skillet (watch for some splattering!), reserving the plate they were on, spread into an even layer and cook until one side is golden and crisp, about 2 to 4 minutes. Using a slotted spoon, transfer the crisped gnocchi back to the plate.

Add the cherry tomatoes to the skillet, stirring to coat them in the oil, and cook until they soften and their skins start to burst, about 4 to 6 minutes. Add the garlic and Sirarakhong Hathei chillies and cook until the garlic is fragrant and light golden, about 2 minutes. Gently press down on the tomatoes with the back of a spoon to burst them. Add the gnocchi back in the pan and gently stir to coat in the sauce.

Transfer the gnocchi to a serving platter or individual plates, garnish with the fried sage leaves, and serve immediately.