For Mexican in Tokyo, I recently discovered a Mexican delivery place called Triceratops Tacos.
http://www.ttttt.jp/
I was fairly impressed with their food, and you can't beat having it delivered to your door through online ordering.
Also if you are here in Tokyo just for a little while I really would suggest trying Shabu Shabu and visiting MK in Shinjuku to do so near Shinjuku-sanchome station. It is a Thai style Shabu Shabu place and they are rather english friendly by having a touch screen menu that can be switched to english to order all your meat and veggies. Its roughly 2000 yen for unlimited shabu shabu and dim sum and soft drinks for two hours.You can have more meat then you will ever know what to do with if you like, and various other great things to try all a click away. Try the spicy chige soup and well it is something I love eating at all times Shabu Shabu is one of my absolute favorite things in Japan and it is a really fun thing to try if you haven't.
Oh and about me here in Japan
What made you interested in Japan?
Honestly I remember being in Junior High School and High school after discovering Japanese Rpgs and old school anime such as Cowboy Bebop and feeling so jealous that I couldn't play or watch them as soon as they came out.My high school at that time offered Japanese classes, and I started to take them. Eventually I ended up doing a few exchange programs including one for a year during my High school days to Shizuoka. After graduating I also came back for another year during university, and now I work in Tokyo teaching at Junior High schools
Why did you learn the language (for those who are not learning, are you interested?)?
At first I wanted to learn it simply to import video games, I remember importing final fantasy 8 and it was a magical experience playing it months ahead of my friends. Eventually my interests broadened and going to high school for one year dramatically helped my Japanese speaking ability
Are you currently living in Japan?
Yes.
How long have you lived in Japan?
Throughout my life roughly 4 years now.
What is your favorite Hotto Motto meal?
I have never been to Hotto Motto to be honest, I recently found a burger place near my house
http://www.bakerbounce.com/ in Sangenjaya in Tokyo that is really good, and even serves root beer.
What is your favorite place in Japan?
I really love visiting Nikko, and I have a special place in my heart for Setagaya ward in Tokyo where i have lived and worked for the last two years as I find the area to be quite comfortable and has a different atmosphere then some of the other areas I feel. Also pokemon is made here.
What is your favorite Japanese food & drink?
Technically it is a chinese food but I love gyoza. Japanese style gyoza is one of my absolute favorite foods followed by karage and sushi.
As for drinks I tend to like the various sours and I am a fan of umeshu. I do like some of the micro brewery beers that have begun to pop up. I like
http://bairdbeer.com/en/ quite a bit to be honest for example.
What is your favorite season to be in Japan?
Spring or fall. I still find it amazing and almost magical to see the cherry blossoms bloom and the world outside is this peaceful rainbow of colors and smells(granted I have to take a ton of allergy medicine at that time of the year though) and fall because it is comfortable and I like some of the seasonal foods that can be found at that time.
Where are you from, and which languages do you speak? (conversational and above)
English and Japanese are the two I have full conversational ability with.
What should we call you if we ever met you IRL?
Rob, I rather not go by my weird username that I started using roughly twenty years ago when the internet was new and I was a child in school, but I still use it.