Destem and mince the Fresno chiles (seeds can be removed to make it less spicy). Set aside.
Wash and dry the blood oranges, then using a microplane or other zester, zest them being careful to avoid the white pith.
In a mortar and pestle or a food processor, add the chopped chilies, blood orange zest, 1 teaspoon blood orange juice, salt, and ½ tsp lime juice and blend or grind until you get a coarse, slightly chunky paste. If the paste is too thick, add a few drops more juice, if it’s too loose, add a small pinch of salt or zest.
Transfer to a small jar, cover, and refrigerate for at least 3 days before using. This helps the flavors meld and deepen. The kosho will keep in the fridge for a couple months.
SHRIMP
To make the marinade, add the olive oil, blood orange kosho, garlic, blood orange juice, and salt to a bowl and mix to combine. Taste for seasoning adding more salt or blood orange kosho as needed.
In an airtight container or ziplock bag add the shrimp and pour the marinade over, using a rubber spatula to make sure all the marinade gets in. Mix the shrimp around ensuring each is coated in the marinade, then leave in the fridge for 1 to 2 hours.
Preheat your grill to medium high heat, either gas or charcoal. Once hot, use a paper towel soaked with olive oil and tongs, to oil the grates of the grill.
Grill the shrimp for 1 to 2 minutes per side, brushing with the marinade before flipping. Once done, the shrimp should be pink and lightly charred. Serve with blood orange wedges and salsa macha if you want extra spice.