In a small skillet over medium heat, add the sesame seeds and sauté until nicely brown, about 5 minutes, tossing often. Remove from the heat and let them cool off for 10 minutes.
Add toasted sesame seeds to a spice grinder and process until fine, about 5 seconds. Transfer to a small bowl and add thyme, sumac, oregano, cumin, salt and lemon seasoning; stir until well blended.
Transfer the spice blend to an airtight container and store in a cool, dark place for up to 3 months. Yields 6 tablespoons.