Basil Pesto

01Ingredients

60g fresh basil leaves, packed
50g pine nuts (or walnuts)
2 garlic cloves
50g parmesan, grated
125ml olive oil
Salt and pepper, to taste

02Method

Toast pine nuts in a dry pan over low heat for 2-3 minutes until golden, watching closely so they don't burn.
Add basil, toasted pine nuts, garlic, and parmesan to a food processor. Pulse until roughly chopped.
With the processor running, slowly drizzle in the olive oil until smooth but still with some texture.
Season with salt and pepper to taste.
Use immediately, or store with a thin layer of olive oil on top to prevent browning.

03Notes & substitutions

Swap pine nuts for walnuts, cashews, or sunflower seeds - all work well.
Swap parmesan for pecorino for a sharper, saltier result.
No food processor? A mortar and pestle works too, and is the traditional method - just expect more effort.
Vegetarian as written (check the parmesan is vegetarian-rennet if that matters to you).

04Common mistakes

Over-processing — pulse rather than continuously blend; over-processing releases bitter compounds from the basil and heats the mixture, dulling the flavour.
Adding oil too fast — drizzling it in slowly while the processor runs helps it emulsify properly instead of separating.
Skipping the toast — raw pine nuts taste flat; toasting them first deepens the flavour.

05Storage & leftovers

Fridge

Airtight container with a thin layer of oil on top, up to 5 days.

Freezer

Freezes well in an ice cube tray, for up to 6 months.

Serving

Stir through hot pasta off the heat, rather than cooking it directly - heat dulls the fresh flavour.

More About This Recipe

06Ingredient notes

Basil. Use leaves only, not stems - stems are fibrous and make the pesto grainy rather than smooth.

Pine nuts. Toasting them first is a worthwhile extra step, deepening the flavour well beyond what raw pine nuts give.

Olive oil. A good everyday olive oil is fine here - saving an expensive one for this doesn't add much once it's blended with everything else.

07Troubleshooting

Pesto is bitter. Almost always over-processing or too much raw garlic - pulse instead of blending continuously, and start with less garlic than you think.
Pesto is too thick. Add a little more olive oil, or a splash of the pasta cooking water if using it straight away.
Pesto has turned brown. Oxidation from air exposure - press a layer of plastic wrap directly onto the surface, or top with a thin layer of oil, before storing.
Pesto separates or looks oily. The oil was likely added too quickly - next time, drizzle it in slowly while the processor is running.

Frequently Asked Questions

Why does my pesto turn brown?

Oxidation from air exposure - basil browns quickly once cut or blended. Storing it with a thin layer of olive oil on top slows this down by sealing out air.

Can I freeze pesto?

Yes - freeze in an ice cube tray for individually portioned servings, then transfer the frozen cubes to a bag for up to 6 months.

Can I use a different nut?

Yes - walnuts, cashews, or even sunflower seeds all work well in place of pine nuts, each giving a slightly different but good result.

Why is my pesto bitter?

Usually over-processing, which releases bitter compounds from the basil, or too much raw garlic. Pulse rather than continuously blend, and start with less garlic than you think you need.