Line a baking sheet with aluminum foil. Then place oven-safe cooling racks on top. Put your marinated beef jerky on top of the cooling racks, ensure that pieces aren't touching or overlapping.
Pre-heat your oven to 350F.
Once pre-heated put your jerky in the oven on the middle rack for 10 minutes.
While your jerky is heat treating, set your dehydrator to 130F.