Trenette al Pesto
Potatoes and green beans cook in the same water as the pasta, in sequence. The potatoes release starch that binds the pesto to every strand. The beans add sweetness. The pesto goes on cold — never heated — and the residual heat of the pasta does the rest. One pot, twenty minutes, the real Genoese method.
Equipment
- Large pot for the pasta
- colander
- Ladle or heatproof mug for reserving pasta water
- Large mixing bowl or the drained pot for tossing
Ingredients
- 400 grams trenette pasta preferably homemade
- 200 grams waxy potatoes peeled and cut into 2cm cubes
- 150 grams fine green beans trimmed and halved
- 4 tbsp pesto alla genovese
- salt
Instructions
- Bring a large pot of well-salted water to the boil. Add the potato cubes and cook until soft but still firm.
- Add the green beans to the same pot and cook for a further 2 minutes.
- Add the trenette and cook until al dente, checking the packet time and tasting 1 to 2 minutes early. Before draining, scoop out a full mug of the starchy cooking water and set it aside.
- Drain the pasta, potatoes, and green beans together. Return everything to the pot off the heat.
- Add the pesto and 2 to 3 tablespoons of the reserved pasta water. Toss well until every strand is coated and glossy. Add more pasta water gradually if the sauce is too thick.
- Serve immediately in warmed bowls.
Notes
- Never heat the pesto. The residual heat of the pasta is all it needs.
- The potatoes are not optional - their starch binds the sauce to the pasta.
- Reserve more pasta water than you think you need.