Although the modern foodie – especially those who write restaurant reviews – seem to think mash should be ultra smooth & gloopy I know that it should feel much more substantial to give the right degree of comfort & consolation.
The answer lies in ignoring the manufacturer’s cooking instructions.
Peel off the film from the top of the tub & stir up the contents thoroughly with a fork – you are aiming break up the great homogenous blob & to introduce air. Do not flatten or smooth over the top – the peaks will get nicely browned.
Then cook in the oven as instructed except that you should not replace the film. The result will be a drier, meatier, more satisfactory mash.
I cannot think of any reason why this ignoral of the manufacturer’s instructions should pose any threat to health (it’s not like doing an inadequate job of reheating the remains of last night’s curry still in its plastic container). For some dishes the manufacturer instructs you to remove the film before cooking anyway, & as far as I can work out leaving the film on is only necessary to retain moisture where it is needed, so that a dish of what is supposed to be spag bol does not turn into something resembling old boot leather.
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The real problem with ready meals?
The real problem with ready meals?