In a dry pan, set the stove over medium-high heat, toast the white sesame seeds and shake the pan every minute for 5 to 7 minutes until golden brown and fragrant. Set aside.
Repeat the same procedure for the black sesame seeds. Combine the toasted sesame seeds in a bowl.
In a dry pan, set the stove over medium-high heat, toast the drained tuna flakes and constantly shake the pan until completely dry.
Cut the nori sheets into small pieces. In a pan, toast the nori sheets for 3 minutes over medium heat. Set aside.
In a bowl, mix roasted and raw sesame seeds, tuna. Season with salt. Mix thoroughly.
Optional: you can also add chili flakes.
Store in a an airtight container. You can keep it up to 1 year or more as long as you store your furikake in a cool dry place.