Preheat the oven to 350°F.
To make the crust, stir the flour, salt, and olive oil together in a large mixing bowl. Gradually mix in the ice water, until the mixture starts to pull together to form a loose ball. Trickle in a little more ice water if necessary, Use your hands to pat the mixture into a firm ball, wrap in plastic wrap, and chill in the refrigerator for at least 30 minutes.
To make the filling, heat the canola oil in a large skillet over medium-high heat. Add the onion and cook, partially covered, stirring often, until softened and translucent, about 7 minutes. Add the speck and spinach and cook for 5 minutes longer. Season with salt and pepper to taste. Set aside to cool.
Break the eggs into a large mixing bowl and beat well. Stir in the cheese, nutmeg, ½ teaspoon salt, and ½ teaspoon pepper. Stir in the cooled spinach mixture.
Unwrap the chilled ball of dough and place on a clean, well-floured work surface. Use a rolling pin to roll out the dough into a disk about ¼ inch thick and 9 or 10 inches in diameter. Press the dough into a 9-inch Pyrex pie plate. Use a small fork to make a bunch of shallow dents in the bottom of the crust.
Bake the crust for 15 minutes; then remove it from the oven, pour in the egg and spinach mixture, and bake for about 35 minutes longer, until the center is firm to the touch and the top has browned lightly. Allow to cool for at least 10 minutes before serving so the quiche holds together when sliced. Before serving, garnish with more freshly grated cheese if you like.