Add the potatoes to a large pot of salted boiling water and cook for 15 minutes, or until they can be easily pierced with a knife. Remove from the heat, drain, season with salt and pepper and mash together with a little olive oil and milk - to loosen if necessary. Set aside.
Meanwhile, fry the onions over medium heat with 1 Tbsp olive oil. Cook for 2-3 minutes until softened then add the garlic and herbs and fry for another minute.
At this stage preheat oven to 200°C.
Add in the chicken to the onions and cook until just cooked through, about 4 minutes.
Add in the tomatoes, chutney, Worcestershire sauce and a pinch of salt and pepper, and leave to simmer for a further 10 minutes.
Remove from the heat, check the seasoning, add in the frozen peas and pour into a medium-sized ovenproof dish.
Top the chicken filling with the potato mash, and a sprinkling of cheese if you like, then bake for 10-15 minutes or until the mash topping is lightly golden.
Reprinted with permission of Sarah Graham. To see more recipes, click here.