Slice the russet potato into 1/2-inch thick wedges and toss with 1 teaspoon of avocado oil and a pinch of the sea salt.
Place the potato wedges in an air fryer basket at 400°F and cook for 15-20 minutes, shaking halfway through until they are golden and crisp.
Pat the cod fillets very dry with paper towels and season both sides with a portion of the sea salt and black pepper.
In a shallow bowl, whisk together the flour, baking powder, garlic powder, paprika, and the remaining salt and pepper.
Slowly pour the light beer into the flour mixture, whisking gently until a smooth and bubbly batter forms.
Heat the remaining 1 teaspoon of avocado oil in a large non-stick skillet over medium-high heat.
Dredge each cod fillet into the batter until fully coated, then carefully place them into the hot skillet.
Cook the fish for 3-4 minutes per side until the batter is deep golden brown and the fish is opaque and flakes easily.
Serve the crispy beer-battered cod immediately alongside the hot air-fried chips.