Carnitas Roasted in Banana Leaf

6# Boneless Pork Shoulder.
S&P.

Puree:
2T Achiote Paste.
1Tbsp Chopped Garlic.
1/4C Orange Juice.
1/4C Lime juice.
2t Mexican Oregano, toasted.

1 white onion, chopped
1 pkg banana leaf