Place racks in upper and lower thirds of oven; preheat to 350°. Line 2 baking sheets with parchment paper or nonstick baking mats. Mix 1 large egg, 1 cup smooth almond butter, 1 Tbsp. vanilla extract, 1 tsp. baking soda, and ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt in a large bowl with a rubber spatula until combined. Add 1 cup (150 g) coconut palm sugar or ¾ cup (packed; 150 g) light brown sugar and mix until a soft dough forms. (It will be very thick, so use your hands if needed.) Add ¾ cup mixed seeds (such as sesame, pumpkin, sunflower, hemp, and/or flaxseed; coarsely chopped if large) and mix until evenly incorporated.

Using a #16 cookie scoop or ¼-cup measuring cup and working one at a time, scoop out dough into portions and roll into smooth balls. Divide between prepared baking sheets, spacing at least 2" apart (about 6 per sheet). Press down to flatten balls into about ½"-thick rounds. (If using particularly dry almond butter, your dough might crack. But don’t worry; once baked, the cookies will be just fine.) Bake cookies, rotating baking sheets top to bottom and front to back halfway through, until slightly puffed and cracked, 11–15 minutes. Let cool on baking sheets. Do Ahead: Cookies can be baked 3 days ahead. Store airtight at room temperature, or freeze in a resealable plastic freezer bag up to 4 months. If freezing, let sit at room temperature about 20 minutes before eating.