Preheat your air fryer to 400°F.
Cut the potato into thin wedges and toss them in a bowl with 1 teaspoon of avocado oil and a pinch of sea salt.
Place the potatoes in the air fryer basket in a single layer and cook for 18-20 minutes, shaking halfway through, until golden and crisp.
While the chips cook, whisk together the flour, beer, and a pinch of salt in a shallow bowl until a smooth, thin batter forms.
Pat the cod fillets completely dry with paper towels and season both sides with black pepper.
Dip each cod fillet into the batter, allowing the excess to drip off, and place them on a plate.
Lightly brush the air fryer basket with the remaining 0.5 teaspoon of avocado oil, place the fish inside, and air fry at 375°F for 10-12 minutes until the coating is crispy.
In a small bowl, stir together the Greek yogurt, capers, lemon juice, and dried dill to create the tartar sauce.
Serve the hot beer-battered fish immediately alongside the potato chips and the chilled tartar sauce.