- Preheat outdoor grill to medium-high heat (400-425ºF). Lay 4 large pieces of foil on a work surface. Add cubed chicken to a medium bowl and toss with ¼ cup of teriyaki takumi. Divide chicken over the 4 foil packets, placing a portion in the center of each one.
- Divide bell pepper, red onion, and asparagus and add a portion to each piece of foil.
- Fold up edges of foil and pinch to secure, leaving a bit of space on each end for air to flow. Grill the foil packets for 20-25 minutes with the seam side facing up for venting. Remove foil packets from grill using tongs and place on a sheet pan. Cool for 5 minutes.
- Open foil packets and drizzle with remaining teriyaki takumi. Sprinkle with toasted sesame seeds. Serve directly in the foil packets with ½ cup of rice per serving, or serve plated over rice.