Sauté the aromatics: Warm the olive oil in a large frying pan over a medium heat. Once the oil shimmers and smells fragrant, add the diced onion. Cook for 4–5 minutes, stirring occasionally, until the onion turns translucent and softens, and you hear a gentle sizzle. The kitchen will begin to smell sweet and savoury.

Bloom the spices: Add the minced garlic, ground cumin, and smoked paprika. Stir constantly for about 30 seconds. You’ll notice the spices darken slightly and release a heady, warm aroma. This step is crucial for depth of flavour.

Build the chipotle base: Tip in the chopped chipotle peppers and the adobo sauce. Stir well, letting the paste cook for 1 minute. The colour will deepen to a rich, brick red, and the heat will become wonderfully apparent in the air.

Add the beans and liquid: Pour in the drained black beans, vegetable stock, and tomato purée. Stir everything together until the beans are evenly coated in the spicy red sauce. Bring the mixture to a gentle simmer — you should see small bubbles breaking the surface.

Mash and thicken: Using a potato masher or the back of a wooden spoon, mash about half of the beans directly in the pan. Leave the rest whole. Continue to cook for 5–7 minutes, stirring occasionally, until the liquid thickens to a creamy, spoonable consistency. The texture should be cohesive but not dry; a slight gloss from the oil indicates it's ready.

Finish with lime: Remove the pan from the heat. Squeeze in the lime juice and stir. Taste and adjust seasoning with salt and pepper. The filling should taste smoky, tangy, and gently spicy, with a creamy contrast from the mashed beans.

Warm the tortillas: While the filling rests, warm your tortillas. You can do this in a dry frying pan over a medium-high heat for about 30 seconds per side, until they blister and become pliable. Alternatively, wrap them in a clean tea towel and warm them in a low oven (140°C) for 10 minutes. They should feel soft and flexible, not brittle.

Assemble the tacos: Spoon a generous portion of the spicy chipotle black bean filling down the centre of each tortilla. Top with your chosen garnishes — a few slices of avocado, a sprinkle of fresh coriander, or a crumble of feta. Serve immediately while the filling is still warm and the tortillas are soft.