Peel and finely chop the shallots and garlic. Grate the zucchini. Finely chop the thyme leaves. Drain, rinse and dry the prawns. Grate the Parmesan. Boil the measured water and dissolve the vegetable stock cube in it. 

Heat a large pan over a medium heat with a drizzle of olive oil. Once hot, add the prawns and the garlic with a generous pinch of salt and cook for 2 min or until the prawns are cooked. Transfer the prawns and garlic to a bowl. 

Return the pan to a medium-low heat with another drizzle of olive oil (no need to wash it!). Add the shallots and cook for 6 min until very soft. Once soft, add the zucchini and thyme and cook for 2 min further. 

Add the orzo and stock and cook, covered, stirring occasionally, for 12-15 min or until the orzo is soft. 

Once soft, season the orzo with a very generous squeeze of lemon juice and a grind of black pepper. Add the Parmesan and prawns along with any garlic, oil or juices left in the bowl.

Divide the orzo among plates and crumble the feta over the top.