Less messy to clean up after than the liver recipes but not a great baking smell in the kitchen but HUGELY popular with my boys: 2 tins mackerel 1 tin chopped tomatoes 1 egg about 8 oz rice flour I use rice flour as barney has allergies and it's much easier for dogs to digest than wheat but if your dog is ok with normal biscuits you can use wheat flour. put the contents of the tins into the food processor with the chopped tomatoes. I use the value brand so strain off excess water first, if using a premium brand that step isn't necessary. If you don't you'll simply need more flour to stiffen up the dough. blend the fish and tomatoes until quite smooth. Add the egg and blend again. If your processor is big enough you can gradually add flour to make a dough. For me I turn liquid into a mixing bowl then stir in the flour until it makes a soft dough. Then knead together with more flour until it is dry enough not to stick to a surface/hands/rolling pin. dust your board with flour and roll out to about 1/4-1/2 inch thick. The thicker the dough the longer the cooking time and there will be fewer biscuits. Cut into shapes using cutter, or a shot glass works well for lab bite size. Re roll scraps and cut out until all used up. Or you can simply cut into squares with a knife. put on baking sheets and cook in moderate oven about 180 degrees until crisp. They don't change colour much and don't spread so you can put them very close together on the sheet. Cook for 20 - 30 mins depending on thickness. For extra crunch simply turn off the oven and leave to cool slowly inside for several hours or overnight. Makes a lovely orangey coloured biscuit that generates lots of licked lips, prompt recall and even a lovely heel from a Barney dog - can't be bad!