Add plain flour and salt and pepper to beef and shake to coat/flour. I do this in a bag to make it easy. Then add this floured meat to the slow cooker
Add all the vegetables to the slow cooker and mix with meat.
Combine tomatoes, soup and sauce, pour over and stir to combine.
Do not add the peas or the cornflour mix until later
Cook on HIGH for 6 hours initially, then add your peas.
At this point, then stir through your conflour mix to thicken the casserole. Now you'll make your dumplings... To make dumplings, combine the flour, mustard, and herbs in a large bowl. Add the butter and use your fingertips to rub in until crumbly. Stir in the parmesan, then make a well in centre. Add milk and use a knife to combine until mixture starts to clump together.
Gently gather dough together and make golf ball sized dumpling balls (I made 14) . Gently drop them on top of casserole, spaced apart, as they will expand.
Cover with tea towel trick and continue to cook on low for another 60mins or until dumplings are cooked. Serve a hearty bowl of casserole topped with 2-3 fluffy dumplings per bowl