In a small, dry (no added oil) skillet, on medium-low heat, add the white and black sesame seeds. While constantly moving the seeds around, toast the seeds for 1 to 2 minutes being careful not to burn them.
Add the toasted sesame seeds to a small bowl.
Add the poppy seeds, onion, garlic, and sea salt to the bowl with the sesame seeds. Mix well.
Transfer the seasoning blend to a jar with a tight fitting lid.
Notes
You can skip the toasting of your sesame seeds if you want. Toasting the seeds adds a great flavor but can be omitted and the seasoning blend will still be tasty.
You can use a 2 cup glass measure cup with a pour spout to mix this seasoning blend in. This makes it easier to pour into your storage container (½ pint mason jar) after you mix the spices together.
You can substitute coarse kosher salt for the coarse sea salt if you are unable to find the sea salt in your local grocer.