Step 1

Preheat oven to 220°C. Dry-roast cumin and coriander seeds in a small frying pan over medium-high heat until fragrant, then crush with a mortar and pestle. Add garlic and 1 tsp sea salt, and pound to a coarse paste, then stir in half the olive oil. Transfer to a bowl, add steak and massage paste into meat. Set aside.

Step 2

For salsa, heat a barbecue or char-grill pan to medium-high and barbecue corn, turning occasionally, until charred and just cooked through (5-8 minutes). Cool briefly, then slice off kernels and place in a bowl with remaining ingredients, toss to combine and season to taste.

Step 3

Brush steak with remaining olive oil, season well and grill, turning once, until browned all over (4-5 minutes each side). Transfer to a roasting tray and roast until cooked to your liking (5-7 minutes for medium-rare). Rest for 10 minutes, then thinly slice.

Step 4

Blend sour cream and chipotle chilli in a small food processor to combine and season to taste.

Step 5

Char tortillas (30 seconds to 1 minute each side), top with sliced steak, chipotle sour cream and corn, radish and coriander salsa, scatter with extra coriander, season to taste, and serve with lime wedges and hot sauce.