Hi EuanW, I tend to disregard the menu wordings of dishes as I'm sure you will have came across word for word descriptions across many Glasgow menus.
"special blend of Punjabi spices" seems to feature heavily, which is clearly selected from a drop down menu at the printers.
The masaladar/masalader sauce is definitely an offshoot of a pathia rather than a Punjabi masala. If you play about with the quantities of mango chutney, ketchup, base gravy, sugar& lemon,, you will get close to what your after.
Of course, if you don't know your local restaurant or t/a's gravy recipe, it won't be the same thing.
Depending on how much pathia/chasni/masalader they knock out, they will normally have a ready made sweet and sour paste to make all those 3 dishes.
The jhal/ tandoori/red sauce paste is not what goes in a masaladar. For example,that would be in a Japuiri curry, which you've probably had one being Glaswegian
Regards
ELW
*I'm in Glasgow myself, so if you want to post your Glasgow restaurant / t/a good & bads I'm all ears