Recipe adapted from 101cookbooks, recipe by Michel Nischan from his book Homegrown Pure and Simple
Makes 12 muffins

If you are looking for a leisurely weekend recipe to lose yourself in, this should do the trick. It’s a bit complicated but well worth the effort.

Flavorless vegetable oil spray (or grapeseed or rice oil in a mister or spray bottle), optional
1 pound butternut squash, peeled, seeded, and cut into small cubes (about 3 cups)
1 teaspoon coarse sea salt
8 black peppercorns
2 cinnamon sticks
2 tablespoons coriander seeds
4 cups freshly pressed apple juice (or apple cider)
1 cup raw cane sugar
2 large egg yolks
1/2 cup organic applesauce
1/4 cup grapeseed, rice oil or clarified butter at room temperature
4 large egg whites
2 cups spelt flour
2 1/4 teaspoons baking powder
1 teaspoon baking soda
1 teaspoon fine sea salt

Preheat the oven to 350° F.
Spray a 12-cup muffin tin with the oil, or put paper liners in the cups. Spray a rimmed baking sheet as well, or line with parchment paper.
Toss the squash with the coarse sea salt and spread in a single layer ion the prepared baking sheet. Bake for 20 to 30 minutes, or until the squash is cooked through and tender.
Meanwhile, in a saucepan, combine the peppercorns, cinnamon sticks, and coriander over medium-high heat and heat for 2 to 3 minutes, or until the coriander begins to smell like oranges. Remove from the heat. Let sit for 30 seconds, and then add the apple juice. Return to the heat and simmer for 30 to 40 minutes, or until reduced to 1/4 cup and thick. Pour the apple juice through a fine-mesh sieve, discard the whole spices and push the reduced juice through the sieve with the back of a spoon, if necessary. Set aside.
Transfer the squash and reduced juice to a food processor and process until smooth.
In the bowl of an electric mixer fitted with a paddle attachment, beat together the sugar and egg yolks on high speed for about 3 minutes, or until light and fluffy. Reduce the speed to low and mix in the applesauce, oil, and butternut squash puree just until blended. Transfer to a large bowl.
Fit the mixer with the whip attachment and clean and dry the bowl. Add the egg whites to the bowl and beat on medium-high speed until very foamy, but not quite soft peaks.
In another bowl, whisk together the flour, baking powder, baking soda, and the fine sea salt. Add to the batter and stir just until mixed, then fold in the egg whites just until blended. There will be some white streaks in the batter, which is fine.
Spoon the batter into the muffin cups, filling each one about three-fourths full. Bake for 30 to 40 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Let the muffins cool in the tin on a wire rack for about 5 minutes. Turn the muffins out of the tin and let cool completely on the rack before serving.