Stick turkey breast in the freezer for 20-30 minutes so it firms up. Then use a very sharp knife to slice the breast into thin, 1/8-inch slices. Try to make them as uniform as possible.
Combine turkey slices in a medium-sized bowl with all other ingredients. Stir together and let sit for at least 4 hours or overnight.
Scoop turkey into a colander in the sink and let extra marinade drain off.
Preheat oven to 175ยบ F. Place 2 wire racks over baking sheets and lightly oil them with a neutral oil.
Carefully place turkey slices on wire racks. Make sure no slices are overlapping.
Bake turkey for 2 hours, then flip pieces and bake for 2 more hours. You could go longer if you want the jerky even chewier.
Cool jerky and store in an airtight container in the fridge for freeze for longer storage.