If you make it, you make it big. My place makes $1M in revenue and ~10% profit

But if you don't blow up, the rent will kill you. My friend ran a good place, but it wasn't busy enough to pay the $30k/month rent

The economist and food critic Tyler Cowen often writes that the best food is typically in low-rent areas for precisely this reason. If fixed costs are low, then the restaurant can afford to focus on the quality of the food a bit more. This is particularly true for many varieties of ethnic food, where the restauranteurs may be immigrants without a lot of money to put up, but a rich knowledge of the food from their home country.

You see that a lot in Chicago were good restaurants are often found in weird parts of the city (I'm looking at you 42 grams)

You mention it only cost you 40k to get started; how long did it take to reach $1MM in revenue/10% profits?

We did that in our 3rd year

Is 10% profit considered good? That seems to be a lot of work to just net 100k.

Is that net and your take home?

It's not truly net unless he's paying himself a market rate for the amount of work he's doing (which if he's a programmer, may very well be $0 if everything is run by staff).

10% margin seems great for a restaurant, especially if that's after paying the owner. I've worked in management in restaurants (diners, nothing fantastic but a great way to help pay for school) and profit margins in the low-to-mid single digits before paying the owner is not uncommon.