Until February 15, Liberty Tree is not serving their a la carte lunch. It's the same menu as dinner. Liberty Tree is not a buffet, but a fixed price, fixed menu, all you can eat served at the table family style. The characters currently appearing there for all three meals are Minnie, Pluto and Chip & Dale.
LTT is currently scheduled to go back to its regular times and menus (with no characters) starting February 15 when Crystal Palace reopens.