Rach shares a time-saving hack for guacamole: halve ripe avocados + remove pits, then press onto a cooling rack placed over a bowl to separate from skin.
For the guacamole, place the onions, garlic, jalapeño, juice of 1 lemon and salt in a bowl and let the salt bleed the juices from onions and chili pepper for 10 minutes. Add avocados and cilantro and mash. Add more lemon juice to taste. Mix in chipotle purée or Tabasco and set aside.
Season meat with salt and pepper, and combine marinade: lime juice and zest, beer, oil, garlic, cumin, coriander and puréed chipotle or Tabasco. Coat beef in marinade and let stand 1 hour or several hours refrigerated.