Techniques to toast mate tea leaves The most common way of drinking mate (iles paraguariensis) tea is infusing its green leaves with hot water in a special way (chimarrão).

However, there is also the option to drink the toasted leaves tea. This is specially common in Rio de Janeiro, Brazil.

I want to know the best (and perhaps alternative ways) to toast the mate leaves at home in a way similar to the commercial ones, like "Mate Leão".

Please note that this process is different from the "sapeco" which is a very brief exposure of the green fresh leaves to fire in order to conserve its color characteristics.
There are green teas in China that have a 'toasty' flavour and that is usually achieved through pan frying. I would suggest to try that in a pan at home yourself (without oil). Make sure the leaves are continuously stirred, or they will burn. 

Check for instance this video (at 25 sec) for a demonstration:
https://www.youtube.com/watch?v=tmKkVLadXKQ