Using a stand mixer fitted with a paddle attachment or a wooden spoon and a lot of arm power, cream together the almond butter and the butter until light in color and airy in texture. Add the vanilla and stir to combine.
Whisk the confectioners' sugar with the cinnamon.
Next, pour in the confectioners' sugar, a little at a time, and beat until the sugar is incorporated and the dough holds together when compacted. If the mixture is still wet—as might be the case if you're using almond butter with a lot of natural oils—you'll need to add more confectioners' sugar. Make sure to add the sugar slowly: You can always add more but you won't be able to go back.
Using your hands or a cookie scoop, shape the dough into small balls that are about the size of 2 compacted tablespoons. Place each ball on a parchment-lined baking sheet. Put the baking sheets in the freezer to firm up for 20 to 30 minutes.
When the peanut butter balls are sufficiently chilled, melt the chocolate in the microwave in 20-second intervals until it's smooth and glossy.
Dip each frozen ball into the melted chocolate, coating each as much as you'd like. Once all of the peanut butter balls have their chocolate coats, lay them back to rest on the baking sheets and spear each one with a toothpick for a cleaner eating experience.
Sprinkle the buckeyes with flaky sea salt while the chocolate is still melty—that'll help the salt to adhere.
Put the sheets back into the freezer for 5 to 10 minutes, until the chocolate has set and the buckeyes are firm. Sneak 1 or 2 for yourself, then wrap them up for your valentine. (And save any extra in the refrigerator for the next couple of weeks. Or keep them in the freezer for whenever you need a spontaneous gift.)