Prepare the slow cooker base: In the bottom of your 5-6 quart slow cooker, whisk together the chicken stock, tomato paste, olive oil, minced garlic, smoked paprika, cumin, oregano, chilli powder, salt, and black pepper. The mixture should look a deep, rusty red and smell warmly aromatic of the toasted spices.

Layer the vegetables: Scatter the sliced bell peppers and red onions into the liquid, creating an even bed. They will soften and release their own juices as they cook, creating a fragrant steam.

Add the chicken: Place the chicken breasts on top of the vegetables, nestling them down slightly so they are partly submerged in the seasoned liquid. The raw chicken should feel firm and cool to the touch.

Cook low and slow: Cover the slow cooker with the lid and cook on low for 6-7 hours, or on high for 4 hours. Do not lift the lid during the first 3 hours, as this releases valuable heat. You will know it is ready when the kitchen fills with the scent of roasted peppers and cumin, and the chicken shreds easily with two forks.

Shred the chicken: Once the chicken is fork-tender and has an internal temperature of 74°C, carefully transfer it to a cutting board. Use two forks to pull it apart into bite-sized shreds. The meat should be moist and almost falling apart on its own.

Finish the fajita filling: Return the shredded chicken to the slow cooker and stir it into the softened peppers and onions. Squeeze the lime juice over the top and stir again. The filling should look glossy and be coated in a silky, spiced sauce.

Warm the tortillas: Just before serving, warm your tortillas. I do this by placing them directly over a gas flame for about 15 seconds per side, until they blister slightly and smell toasted. Alternatively, wrap them in foil and heat in a 180°C oven for 10 minutes.

Serve immediately: Spoon the hot, fragrant filling into the centre of each tortilla. The contrast of the warm, soft tortilla with the juicy chicken and tender peppers is the goal here.