Preheat oven to 200 degrees C
Place the romanesco, cauliflower, garlic cloves, chilli, lemon zest and 60ml olive oil in a bowl and toss to coat
Place on a baking tray and roast for about 20 – 30 minutes or so until the romanesco and cauliflower is golden and the edges starting to crisp and caramelise
5 minutes before the vegetables are cooked, cook the pasta in a large pot of boiling salted water for 8 minutes or until al dente
Drain the pasta and return to the pot
Squeeze the roasted garlic out of the skins, place in a small bowl and mash with a fork
Add the lemon juice and olive oil and mix until it starts to thicken
Add the roasted romanesco and cauliflower (include all the roasted bits in the tray) and the lemon and garlic mixture to the pasta and toss to combine
Add a splash more olive oil and lemon juice if the pasta is a tad too dry
Season and add a sprinkle more chilli flakes if desired and serve