Cinco de Mayo is coming fast, and to get ready for it Midtown Mexican Toloache is going loco for avocados. For the week (Monday, April 28th–Monday, May 5th) leading up to the anniversary of the Battle of Puebla, not only is chef Julian Medina adding a special à la carte menu starring Hass Avocados from Mexico – including avocado-and-jicama ravioli, avocado "fries" (breaded avocado slices) and avocado cheesecake – but he's also doing a free tasting and guacamole demo to kick the whole thing off on this Monday. Guests who show up at the free event will get to meet and chat with the chef, watch a demonstration of the art of making guac and eat their fill of the delicious green stuff. The first 20 to RSVP will also get a free Cinco de Mayo "fiesta kit" complete with chips, salsa, recipes, avocados and a party favor; for each person who attends, Hass Avocados from Mexico will donate $10 to City Harvest (5:30 PM; reservations recommended, 212-581-1818).