Pasta with anchovies and roasted peppers

Anchovies go well with green vegetables (here, for example). But they also go with mushrooms (here), and with peppers. I put together this dish last night: it does not need the spring onions, which I used because I had them in the house; I included chillis because I always do. The spaghetti worked well, despite the usual advice that cream sauces suit shapes such as penne better. For two.

2 red peppers
I tbsp olive oil
4 spring onions, sliced (optional)
I clove garlic, chopped
200 ml double cream
I tin anchovies, drained
1 or more dried chillis according to taste, whizzed (optional)
Pepper
250 g spaghetti

Roast the peppers in a gas mark 6/200 C oven for 20 to 30 minutes until the skin blackens. Allow them to cool. Peel, deseed and slice them, retaining the juice. (I break the peppers apart with my hands above a bowl, discarding into it skin, seeds and juice.)

Soften the spring onions (if using) and the garlic in the olive oil. Pour in the juice from the peppers through a sieve, allowing it to bubble and thicken for a minute or two; pour in the cream, the anchovies, and the chillis if using. Grind over the pepper. Allow this sauce to bubble and thicken. (The anchovies should melt.) Tip in the strips of pepper, and give them time to warm.

Meanwhile, cook the spaghetti. Drain it, and toss it through the sauce.