My general rule for restaurants that also do takeaways is to try the restaurant first. If you like the menu, the service and above all the food then take a copy of the takeaway menu and order the same thing as a take away and see what arrives.
If the takeaway version is as good as the restaurant version then you can be sure that the staff and chefs take their job seriously.
The other rule I have when going to a new restaurant for the first time is to order one of the staples of that type of cuisine and something off of the ‘Chefs specials’. The staple will give you a good guide to how good the chef is and a good indication of the chefs training.The special will showcase the chefs skills.
Let’s consider an Indian restaurant, staples like Saag Paneer, Chicken Tikka or Chicken Korma are pretty much standard on all Indian restaurant menus. Choose one, or two if you are hungry and see if the quality is up to the standard you would expect.
Now when you order the takeaway version, ask about expected delivery times and keep an eye on the clock. I don’t mind a restauranteur saying they are busy and it will be 90 minutes for the delivery, but I do expect the timing to be accurate.
Once you are happy that the chef is up to the standard you are confortable with, try the restaurant or the takeaway on different days, that will tell you if they have a Number Two chef working and when. You may find the food differs between chefs.
Now that you are comfortable with the quality of the food, start exploring the Chefs Specials, this is usually where the talented chefs show off their skills and their regional specialities.
There was a Restaurant in Muswell Hill, London that had a superb chef, one of his specials is something I continuously went back to the restaurant for, even after I stopped living in the area.
Explore your favourite cuisine with a chef that has skill and talent, it will make you and the restaurant happy !