To make the Argentinian Chimichurri sauce: In the bowl of a food processor, add the parsley, oregano, garlic, lemon juice, olive oil and red chile pepper. Process until smooth to your liking. Season with the sea salt and balance the consistency of the chimichurri sauce with more lemon and olive oil as desired.
Make the lime black rice in advance and refrigerate until needed.
In a large bowl toss together the shrimp with the olive oil, garlic powder, onion powder, paprika, oregano and red pepper flakes. Season well to your taste with the sea salt.
Preheat a cast iron griddle on medium high flame, and grill the shrimp for about a minute on each side until it curls up and turns pink; making sure not to overcook it.
Meanwhile make the Argentinian chimichurri sauce: add the parsley, oregano, chile pepper, olive oil, lemon juice and garlic to the bowl of a food processor. Process until smooth to your liking. Season to taste with the sea salt and more lemon juice.
Char the corn tortillas on a low open flame to your liking and assayable your tacos: tortilla, black rice, grilled shrimp, chimichurri sauce, a good squeeze of lime juice. Garnish with red chile slices and edible flowers. Serve with extra chimichurri sauce and lime wedges on the side.