Turn on toaster oven to the lowest setting.
Zest lemons until you have approximately 2 tbsp of zest.
Combine with freshly ground pepper.
Spread mixture onto a parchment or foil lined baking sheet. Bake in toaster oven until the lemon zest is completely dry (approximately 30 minutes). Check on the seasoning occasionally to make sure the zest doesn't burn.
Using a spice grinder, crush mixture until you reach the desired texture. Ideally you'd want a bit of a coarser texture so do not grind info a fine powder.
Add salt 1 tsp at a time until a suitable balance is reached.
Store in an airtight container or resealable bag.