Combine currants and bourbon and let set in a jar to marry flavors for at least three hours to up to several days. Or, if needed more quickly, bring bourbon to a simmer, turn off heat, add the currants, lid and set to steep for about an hour. Drain and set aside.

Preheat oven to 350F (180C) and set oven rack in the upper third of the oven. Line two cookie sheets with parchment paper. Spread walnuts on a small sheet pan and toast for 8-10 minutes or until fragrant. Set aside.

Place the sugars in a large bowl and stir in the melted butter. Whisk in the egg and vanilla. Place a sifter over the bowl and sift in the teff, corn starch, arrowroot (or tapioca) salt, baking soda and nutmeg. Stir vigorously to combine the ingredients. Stir in the oats, currants and walnuts. The dough can be chilled for several days at this point; bring back to room temperature before proceeding to the next step.

Scoop the dough using a #20 large ice cream scoop (3 Tbs each) and place them on the prepared cookie sheets spacing them 2-3" (5-7.5 cm) apart. (see note for freezing tips). Bake for 15-17 minutes until cookies are golden and crisp around the edges. Cool on cookie sheet. They will firm up as they rest.

Store in a covered container for up to four days.