Add 1 inch of water to a large stock pot lined with a steamer basket and bring to a boil. Add the cauliflower florets to the basket, cover with a lid and steam until fork-tender, 12-15 minutes. Let the cauliflower cool to the tough, transfer to a nut milk bag set over a bowl and squeeze out as much liquid as possible.

Transfer the drained cauliflower to a food processor and blend until completely smooth. You may need to wipe down the sides several times.

Place the cassava flour on a large cutting board or clean countertop and make a deep well in the middle. Add the blended cauliflower, egg, and 1 teaspoon kosher salt. Using your hands or a bench scraper, continuously fold the mixture over onto itself from all sides until all of the flour is incorporated and a ball of dough forms. It should be smooth, soft and hold its shape when pressed with your finger. If the dough is too sticky, add a small amount of cassava flour and repeat.

Divide the dough into four equal-sized pieces and roll into individual balls. Roll each ball of dough back and forth into a ¾-inch-thick rope. Cut the rope into individual gnocchi around 1-inch long and dust with a little bit of cassava flour to prevent sticking. Set aside.

Fill a stock pot with water and bring to a boil. Add 2 teaspoons kosher salt to the water and carefully add the gnocchi. Cook until the gnocchi float to the surface, around 2 minutes. Cook an additional 2 to 3 minutes or until the gnocchi are cooked through yet still a little firm and springy.

Meanwhile, preheat a separate skillet over medium heat. Add the olive oil and butter and heat until the butter has melted and turned golden in colour. Add the sage and cook, stirring occasionally, until golden brown and crispy, around 2 minutes. Drain the gnocchi and add them to the pan. Cook, tossing occasionally, until the gnocchi turn golden brown and slightly crispy all over, around 4 minutes total.

Transfer the gnocchi to individual serving bowls. Season with flakey salt and freshly-cracked black pepper to taste. Garnish with freshly-grated Parmigiano Reggiano and serve immediately.