Hi
I have never tried this before, but if you find it too runny when it has finished cooking you can thicken it by adding cornflour and simmering on the hob for a short time. I have a slow cooker that is actually just like a big saucepan that sits on a hotplate, so it can be transferred directly on to a hob making it very easy to do. If you have the other type of slow cooker which can't be used on a hob you will have to transfer to a saucepan. If you want to add flavours why not try seasoning with a small amount of chilli probably add some garlic if you like it. Mixed herbs are another good way to add flavour too.