Slice the fillets into 1/2" pieces, put them in a medium mixing bowl.
Mix together the cumin, paprika, chilli powder, garlic powder and oregano.
Coat the fish in oil and the lime juice then toss with the spice mix to fully coat. Cover the bowl with plastic wrap and refrigerate for at least 15 minutes.
Make the guac according to the instructions above.
Mix together the sour cream and sriracha til fully combined.
Saute the fish on medium for 5-8 minutes til flaky.
Build your tacos!