6 garlic cloves, peeled
1 grapefruit, juice only
2 limes, juice squeezed, reserving the shells
2 large oranges: grated zest of 1 orange, juice and squeezed shells of both
2 tbsp Seville orange marmalade
2 tbsp freshly ground black pepper
1 tbsp ground cumin
1 tbsp olive oil
1 tbsp dried or freshly chopped oregano
good pinch sea salt
1 tbsp soy sauce
50ml/2fl oz vegetable stock
cooked rice or warmed tortilla wraps, to serve
600g/1lb 5oz skinless, boneless pork shoulder