This is a neat trick where you put the custard powder in the flour mix when making the muffins. The rhubarb provides great colour as well as flavour.
Yummy! Really nice muffins, only took 15min in my oven. Didn't add colouring but they were an attractive 'custard' yellow without it. - 22 Feb 2012
Nice Muffins, everyone like them - 12 Nov 2011
FABULOUS RECIPE!!!! I'd run out of muffin cases, so used a lined loaf tin instead and cooked it for 55 min. It is delicious! May use a bit of ground ginger next time to add to the flavour. Thank you for posting this recipe! - 10 Oct 2010 (Review from Allrecipes UK & Ireland)