CHEESY CARAMELISED ONION AND PINE NUT PASTA RECIPE

6 tbsp olive oil • 60g pine nuts • 120g ricotta • 1 lemon, zest of all, juice of ½ • 1 garlic clove, crushed • 60g parmigiano reggiano, finely grated • 15g pack fresh oregano, leaves picked • 350g bucatini pasta or spaghetti