Notes
Keeps in the fridge 4-5 days. Reheat in the oven at 175C / 350F for 15-20 minutes with a splash of milk to restore creaminess. The panko topping will re-crisp in the oven. Don't microwave if you can avoid it — you lose the crispy top. Freezes well for 3 months. Thaw overnight in the fridge and rebake.