Peas freeze quickly because they are small. And, because they are small, so are the crystals that form when the water in their taut cells (imagine many minuscule balloons) turns to ice. And small crystals cause far less damage, puncturing and ripping to cell walls, which means that, when the pea defrosts and the ice returns to water, the cell walls are able to hold it, resulting in a firmer pea.
Larger items, on the other hand, see the formation of larger ice crystals, which can puncture the walls (again, imagine minuscule balloons, but this time with lots of tiny rips), making them leaky when they defrost and causing mushy vegetables. This is why peas survive the industrial freezing process so much better than, say, carrots or a slice of aubergine.
Peas also defrost quickly, which is something I am reminded of every couple of weeks when I find a warm bag abandoned on the sofa, having done its job with a swollen ankle or a lump on the head. Yes, the bag could go back in the freezer, but often it becomes our next meal.
This is a dish I started making when my son was young (for me, not for him), having had it made for me by a friend who likes frozen peas even more than I do and refers to them as “the vegetable in frozen armour”, for the way they ride in and save supper. You don’t actually need to defrost the peas (by using hot water or a sprained wrist); they can go straight from the freezer into the hot, softened shallot or onion (just give them an extra minute or so in the pan, stirring until they glisten).
There is a satisfying bit of stove alchemy in this recipe, when the single cream, spoonful of cream cheese and grated cheese thicken into a sauce. The sauce then thickens further on the surface of the pasta. My ideal shape here would be little elbow macaroni (again, for me, not for my son), but a ridged penne also works, as does pretty much any small tube or shell for that matter. As always, I have given specific quantities, but this really is a recipe to be made by eye, using whatever cream and cheese you have in the fridge. The lemon zest is optional, but it adds another dimension and an edge to the sauce.
Not to rush anything, but this is a dish to be eaten as soon as possible, while it is hot and the sauce is thick enough to catch and hold the peas, and creamy enough that the tubes of pasta slide around the bowl or plate.
Pasta with peas, cream, lemon and cheese
Serves 4
3 tbsp olive oil
1 knob butter
1 small onion, or 2 shallots, peeled and finely diced
200g frozen peas, defrosted
Salt
250ml single cream
1 tbsp cream cheese, or robiola
50g grana padano, parmesan or sharp cheddar, grated
Zest of 1 unwaxed lemon
White pepper
400g-500g pasta – elbow macaroni, penne, fusilli, linguine
Bring a large pan of water to a boil ready for the pasta. Working in a frying pan or medium-sized saucepan, warm the olive oil and butter over a medium heat, then add the onion and fry, stirring, until soft and translucent. Add the peas and stir until they glisten.
Add salt to the boiling water, stir the pot, then add the pasta and set the timer for a minute less than the recommended pasta cooking time.
Add the cream to the peas and simmer gently. About 30 seconds before the pasta timer rings, add the grated cheese, lemon zest and some white pepper to the cream and pea mix, then raise the heat slightly and stir constantly, so the sauce bubbles and thickens.
When the timer rings, either use a spider sieve to lift the pasta directly into the sauce, or drain the pasta into a colander (save some of the cooking water), then tip into the pea pan.
Toss everything for about 30 seconds; if the mix seems dry, add a bit of pasta cooking water; if it seems loose, add more grated cheese. The aim is that the sauce thickens on the surface of the pasta and catches the peas. Serve immediately.
