Ingredients
- 60 g fresh basil leaves
- 30 g pine nuts, lightly toasted and cooled
- 1 small garlic clove
- 30 g aged hard cheese (Parmesan, pecorino, or omit for vegan)
- 100 ml good extra-virgin olive oil
- 1 teaspoon spirulina powder
- Juice of half a lemon
- Salt to taste
Method
- In a small food processor, pulse pine nuts, garlic, and cheese into a coarse rubble.
- Add basil, spirulina, lemon juice, salt. Pulse 5–6 times.
- With the motor running, slowly stream in the olive oil. Stop when it's a coarse paste, not a purée.
- Taste. Adjust salt. Decant into a clean jar; cover the surface with a thin film of olive oil to keep the colour.
- Keeps a week refrigerated.
Why this pairing works
Pesto is one of the few cooked-style applications where heating is fine — you toss it through hot pasta off the heat, never simmer it. The garlic, basil, and aged cheese collectively own the flavour space; the spirulina contributes a darker green and a savoury, almost oceanic depth that people notice without being able to name.