Yerba Mate is the native millenary tree "Ilex Paraguariensis" that grows exclusively deep into the southern rainforest, specifically in "Valle del Sur" in Argentina, Paraguay, and Brazil. Its naturally caffeinated leaves are used to make an energizing tea known as Yerba Mate.
It has a traditional way to be prepared (in a mate gourd and "bombilla") but, nowadays it can also be treated as a tea, so it can be steeped in tea bags or strainers, French press or even cold brew.