Rinse the rice until the water runs clear. Put in a small saucepan with 250ml (1 cup) water, cover and bring to a simmer over medium heat. Reduce the heat to low and cook for 12 mins or until tender and the water is absorbed. Turn off the heat and stand, covered, for at least 5 mins.
Step 2 — Prep vegetables
Meanwhile, halve the carrot lengthwise, then thinly slice. Coarsely chop the capsicum. Trim the stems from the snow peas, removing the strings from one side. Crush or finely chop the garlic.
Step 3 — Prep fish
Pat the fish dry with paper towel, then cut into 3cm chunks. Combine the cornflour and half the sesame seeds in a shallow dish and season with salt and pepper. Add the fish and toss to coat.
Step 4 — Cook fish
Heat 2 tbs oil in a large deep frypan over medium heat. Cook the fish, turning regularly, for 4-5 mins until browned and just cooked. Remove from the pan, leaving the oil in the pan.
Step 5 — Stir-fry vegetables
Heat the same pan over high heat. Stir-fry the carrot and capsicum for 2-3 mins until beginning to soften. Add the snow peas and garlic and stir-fry for a further 2-3 mins until the vegetables are just tender.
Step 6 — Get ready to serve
Add the oyster sauce and sesame oil to the vegetables and stir-fry until hot. Add the fish and gently toss to combine. Fluff the rice with a fork. Divide the rice and fish stir-fry among bowls. Scatter with the remaining sesame seeds to serve.