Begin by mixing together the marinade ingredients for the chicken: the chipotle en adobo or chipotle paste, salt, grated garlic, oregano, lemon juice and olive oil. Put it all in a bowl and whisk until it has emulsified together. Take this mixture and rub it all over your chicken. You may want to wear plastic gloves for this part if you are worried about the chilli lingering on your skin. Ensure that the whole chicken is covered, and if you can push some of it under the skin without tearing it, please do! You can do this the day before and leave the chicken in the fridge overnight, a couple of hours before, or just immediately before cooking.
When you are ready to cook the chicken, take it out of the fridge and flatten it out with the heel of your hand. To try and keep the bird flat when you are cooking it, take a long metal skewer and insert it horizontally across the bird so that it goes through the thickest part of both legs.
If you are cooking the chicken in the oven, preheat to 200 celcius. If you are cooking it on the BBQ, try and get it to a medium heat (about 180 - 200 celcius): you don’t want the outside to blacken and burn before the inside is cooked through.
Place the chicken straight onto the bars of the BBQ, breast side up. If you can and your BBQ allows, place a cast iron dish underneath the chicken, about half full with water. This will catch some of the chicken juices and the water will stop those juices from catching and burning. If cooking in the oven, try and replicate this by placing the chicken on a wire rack inside a roasting tin with a little water in the bottom.
Whilst the chicken is cooking, you can make the aioli. This can be done in a food processor, or with a stickblender. Alternatively, it can be done with a whisk and some elbow grease, which is the method I will describe here!
Put the egg yolk and salt in a large bowl and whisk until thickened. This will take about 20 seconds. Add the lemon juice and mustard, along with a teaspoon of cold water. Whisk for another seconds. Begin to add the neutral oil, very slowly, drop by drop, whisking all the time. You need a neutral oil here because it is the main ingredient. If you use all extra-virgin olive oil for example, it will make a bitter mayonnaise that will taste unpleasant!
Continue adding the oil very slowly and whisking. When the mayonnaise begins to thicken, you can add the oil slightly faster, still whisking continuously. When you have incorporated all the neutral oil, you can add 25ml of the other oil for flavour. By the time you have added all the oil, you should have a thick, glossy mayonnaise! Add the garlic, lemon and lime zest, black pepper. Taste and season further with salt if necessary. Let it sit for a while for all the flavours to mingle before testing and possibly seasoning again if necessary.
As the chicken is spatchcocked, it will take less time to cook than if you were roasting it whole. After about 25 minutes, use a pair of tongs to turn the chicken over, so that it is breast side down.
Check the chicken after a further 20 minutes. You can use a temperature probe on the thickest part of the chicken - it needs to reach 73 celcius to be safe to eat. Alternatively, you can pierce the thickest part of the chicken’s thigh to see if the juices run clear (I prefer the temperature probe though, it is more reliable and you can pick up a digital one very cheaply). As well as being cooked through, the skin should be bronzed and crispy - but not burnt.
Once cooked through, let the chicken rest for 10 minutes before serving. Collect the juices from the dish or tray below the chicken. If quite watery, reduce in a pan over a high heat to thicken and spoon them over the chicken once carved and ready to serve.