For the Tequila and Lime Chicken the marinade is added to the half-cooked chicken. Doesn't this introduce bacteria? Should the marinade be divided in half so that some can be added later?
Nigella's Tequila And Lime Chicken (from SIMPLY NIGELLA) marinates a jointed chicken in a combination of tequila, lime, chilli and salt. The chicken is removed from the marinade and roasted for 25 minutes, then the reserved marinade is poured over and the chicken cooks for a further 25-30 minutes. If the marinade is added at the beginning of the cooking time then it evaporated too quickly and leaves a burnt residue in the pan.
It is certainly correct that the marinade could contain bacteria, such as salmonella, once the chicken has been in contact with it. But the chicken is then cooked in a hot oven (220c/425F) so the second cooking time of 25 minutes is enough to make sure that any bacteria present will be killed by the heat of the oven; salmonella is extinguished at temperatures exceeding 60c/140F though it is usually recommended that chicken is cooked to 71c/160F. However any used marinade should never be added to fully cooked meat, fish and poultry. Also if you are regularly basting meat with a marinade during cooking (such as for a barbecue) then it is best to keep a separate portion of marinade for this purpose, to prevent any risk of cross-contamination.