Combine all casserole ingredients in slow cooker and cook on low for 4hrs
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 45-60mins or until dumplings are cooked.
Serve with steamed green veg on the side
This recipe also features on page 148 of our book SLOW COOKER CENTRAL - READY SET SLOW! Available on the shop page of this website.