Steak tacos with chili oil and herb butter

Ingredients:

• 1 large orange, cut in half
• 1 lime, cut in half
• 0.5 tsp ground coriander
• 0.5 tsp ground cumin
• 1 teaspoon ground ancho pepper
• 1 hanger steak weighing 700 g.
• 1 tbsp. apple cider vinegar
• 0.5 tsp sugar
• Half a large red onion, thinly sliced
• 1 teaspoon paprika
• 1 tbsp. vegetable oil + more as needed
• 1 cup loosely arranged fresh cilantro sprigs, plus extra leaves for serving
• 0.5 cups loosely packed fresh parsley leaves
• About 1/4 cup sour cream
• 12 corn tortillas, warmed
• 1 avocado, halved and thinly sliced

Preparation:

1. Bring a medium saucepan of water to a boil. Squeeze half an orange and half a lime into a large bowl and add the coriander, cumin, 0.5 teaspoon ground anchovy, and 1 teaspoon salt. Pierce the steak with a fork and place it in the bowl with the spices, turning to coat; let marinate at room temperature for 15 minutes.
2. Meanwhile, in a medium microwave-safe bowl, combine the juices from the remaining orange and lime halves with the apple cider vinegar, sugar, 1/4 teaspoon salt, and 2 cups water. Microwave until just simmering, about 45 seconds. Add the red onion and let sit, stirring occasionally, until ready to serve.
3. In a small saucepan, combine the paprika with 1/2 cup vegetable oil and the remaining 1/2 teaspoon ground ancho. Bring to a simmer over medium-low heat and cook, stirring occasionally, until the oil is hot and bright red, about 3 minutes. Transfer to a small bowl.
4. Prepare a large bowl of ice water. Add the cilantro and parsley to the boiling water and blanch until bright green and wilted, about 20 seconds. Quickly transfer to an ice bath to cool. Remove the greens from the water and squeeze out as much water as possible.
5. Place in a blender with the remaining 0.5 cups of vegetable oil and blend on high speed until as smooth as possible. Strain through a sieve into a small bowl.
6. In a large cast-iron skillet, heat a little vegetable oil over medium-high heat until very hot. Remove the steak from the marinade and pat dry. Cook the steak, turning once, until well-cooked on the outside and medium-rare on the inside, 5-6 minutes per side.
7. Transfer the steak to a cutting board and let rest for 5 minutes; slice thinly across the grain. Season with additional salt.
8. Garnish 4 plates with a little sour cream, chili oil, and herb oil. Serve 3 steak tacos per serving, topping the tortillas with pickled onions, avocado, and cilantro, drizzled with sour cream, and two flavored oils.