Preheat the oven to 350°F. Spray the mini-loaf pans with non-stick coating (or butter) and arrange on a parchment-lined baking sheet.
Place the cranberries in a small, heatproof bowl and cover with very hot water. Allow to plump for at least 15 minutes while you continue preparing the crisps.
Scatter the pecans in a single layer on a baking sheet and toast them in the oven until fragrant, 8 to 10 minutes. Transfer to a cutting board and roughly chop while still warm. Set aside.
In a large mixing bowl, whisk together the flours, rosemary, baking soda, and salt. Whisk in the brown sugar, making sure to break up any big clumps. Pour the kefir over the flours and stir gently with a spatula until no more dry flour remains.
Drain the cranberries. Add the cranberries, chopped pecans, pepitas, and sunflower seeds to the batter. Stir gently to mix evenly throughout the batter.
Divide the batter evenly between the mini-loaf pans, filling them about 3/4 full. Transfer the baking sheet with loaf pans to the oven. Bake 30 to 35 minutes, until the tops have domed and turned golden brown, and a toothpick inserted into the middle of the cakes comes out clean.
Remove the cakes from the pans and let them cool completely. Transfer to a freezer container and freeze solid, several hours or overnight. If you're planning to freeze the loaves for longer than a day, wrap them in foil before freezing. Loaves can be kept frozen for up to 3 months.
When ready to make the crisps, heat the oven to 300°F. Position one rack in the top third of the oven and a second rack in the bottom third.
Remove one of the loaves from the freezer and slice it as thin as possible using a serrated knife, 1/8- to 1/16-inch thick. Lay the slices in a single layer on a parchment-lined baking sheet—the crackers can be close, but make sure they don't actually touch. Continue slicing additional loaves until you've filled two sheet pans.
Bake the slices for 15 minutes. Flip the slices, and continue baking for another 10 to 15 minutes. The crackers are done when they are no longer pale in the middle, feel dry to the touch, and are curled slightly at the edges. It's okay if they're still flexible in the middle; the crackers will crisp significantly as they cool.
Transfer the baked crackers to a rack to cool completely. Continue baking the remaining slices.
Crackers will keep in an airtight container on the counter for several weeks.
Join our mailing list to receive recipes, news, coupons, and more