Heat a chargrill on high. Add the combined chillies and cook, turning occasionally, for 6 mins or until charred all over. Transfer to a bowl. Cover and set aside for 10 mins to steam. Remove stems, seeds and peel from the chillies and discard. Transfer the chillies to a blender with the stock and tomato. Process until smooth.
Season the beef with salt and pepper. Heat the oil in a large saucepan over medium-high heat. Cook the beef, in batches, turning occasionally, for 4 mins or until brown all over. Transfer to a heatproof bowl.
Reduce heat to medium-low. Add the onion and cook, stirring, for 4 mins or until the onion begins to soften. Add the garlic, cumin, oregano and allspice and cook, stirring, for 1 min or until the mixture is aromatic.
Return the beef to the pan with the chilli mixture and stir to combine. Bring to a simmer. Cover and cook, stirring occasionally, for 1½ hours or until the beef is tender. Stir in the vinegar and cook, uncovered, for 10 mins or until the sauce reduces and thickens slightly. Season with salt and pepper.
Meanwhile, to make the street corn, heat a chargrill on high. Brush the corn with the oil. Cook the corn on the grill, turning every 2 mins, for 8-10 mins or until corn is charred all over. Transfer to a plate. In a small bowl, whisk the mayonnaise, sour cream and garlic until well combined. Brush the mayonnaise mixture over the corn and drizzle with lime juice. Sprinkle the corn with the fetta and paprika.
Divide the rice and beef mixture among serving bowls. Serve with the street corn.
Tip: SERVE WITH... lime wedges and coriander sprigs