In a medium skillet set over medium-low heat, add the mustard seeds, anise seeds, coriander seeds, cumin seeds, fennel seeds, celery seeds and black pepper. Cook, shaking the pan often, until the spices begin to smoke and become golden and fragrant, about 5 minutes.
Turn the spices out onto a large plate to cool, then transfer to a spice grinder or coffee mill and pulverize until fine. Pour into a medium bowl and whisk in the smoked paprika and salt. Store in an airtight container in a cool, dark and dry spot for up to six months. Shake to combine before using.