Preheat oven to 400 degrees.
Cut the squash in half lengthwise and remove seeds.
Place squash halves cut side up on a baking sheet, brush with EVOO, season with salt and pepper.
Roast until fork tender at the thickest part of the squat (about an hour)
Let the squash cool slightly, then scoop out the flesh and place in a food processor. Process until very smooth.
Place squash in the bowl of a stand mixer fitted with the dough hook (or just mix in a large bowl by hand) add in the flax eggs and salt. Add flour, 1 cup at a time, until the dough begins to pull away from the bowl. Add 1/2 cup of parmesan cheese and continue on medium speed until combined. Turn out onto a heavily floured surface and knead until dough comes together. Note: You want your dough slightly sticky but if it is TOO sticky, just add a bit more flour.
Portion the dough into quarters, then roll each into a rope and cut into 1 inch sections to form the gnocchi. Place onto a wax paper, cover until ready to boil.
For the sauce, melt butter in a large skillet over medium heat, then add garlic and sage. Cook until garlic is golden and sage is crispy. I like to remove the fried sage and crush into a light powder to sprinkle across the top of the dish!
Bring a large pot of water to a boil then salt lightly. Add 1 cup gnocchi at a time to the salted, boiling water, then cook at a gentle boil until gnocchi float to the top, about 2 minutes. Transfer using a slotted spoon or spider to your sauce. Cook remaining gnocchi then add to the sauce. Season with salt & pepper then toss to coat.
Portion among bowls and garnish with parmesan and sage dust.