The oil is used to stop the butter from burning, hence just a drizzle is needed.
Cook Time:15 minutes
Total Time:-26063273.75 minute
drizzle of oil
3 leeks sliced into coins about 5mm/ 1/4″ thick
15g fresh thyme, with the leaves removed from the stalks
180g/6oz frozen petit pois or peas
zest of 1 lemon
1/8 tsp salt
freshly ground pepper
25g/1oz grated Parmesan cheese
Heat a large saucepan or frying pan (which has a lid) over a medium heat, and add the butter and oil. Once melted add the leeks and thyme, stir well and put the lid on the pan. Cook for 8-10 minutes, stirring occasionally, and adjusting the heat so the leeks cooks in their own steam without drying out.
until the leeks are soft.
When the leeks are soft add the frozen peas and lemon zest to the pan. Stir well and replace the lid.
After a minute or two, check the peas are cooked and then add the salt, pepper and Parmesan. Stir again and serve.