Put the garlic, ginger, lemon grass, chillies, lime juice, olive oil, paprika and half the coriander into a food processor and blend into a paste. If you don't have a food processor, you can just chop everything very fine.
Cut the chicken into chunks and set aside.
Using a peeler, peel the carrots and courgette into strips.
Heat a little oil in a large pan and add the chicken and cook until ready (around 10 minutes). Once it is cooked, add the Thai paste and cook for 3 minutes. Take out of the pan and set aside.
Put your noodles into a pan of boiling water and cook for 5 minutes.
Put the pan back on the heat and add the carrots and courgette. Cook for 3 minutes.
Once everything is cooked, mix the carrots and courgettes with the drained noodles and put onto a plate and then top with the chicken. Sprinkle with the leftover coriander, radishes and spring onions.
You can make a some herby yoghurt to dollop on top by blending together some Greek yoghurt, red chilli and coriander.