To make the ice cream:

1. To make the ice cream, mix the condensed milk, yoghurt, olive oil and salt in a bowl and whisk till smooth.
2. Add the cream to a separate bowl, then whisk till it begins to thicken to a soft peak stage. Fold the cream into the yoghurt mix in 3 stages, aiming to keep as much air in the mix as possible. If the cream is a little stiff, you might need to gently whisk it to remove any lumps. Pour everything into a plastic 1.5 litre container and press cling film or baking paper onto the surface, then place in the freezer for a minimum of 5 hours. Depending on how long it has been in the freezer, you will need to allow it to soften a little before serving. If frozen solid, it will need between 10-20 minutes.
3. When the ice-cream has softened, either scoop out or cut a slice of ice cream and sandwich between 2 oat cookies and repeat as required.

To make the Oat Cookies:

1. Preheat the oven to 180C.
2. In a bowl mix together the self-raising flour, oats, soft brown sugar and salt until combined. Beat the egg in a sperate container, add the olive oil, then add to the dry ingredients and mix until combined.
3. Using a tablespoon scoop, scoop the dough onto a baking sheet lined with parchment paper or silicon mat and flatten slightly. Bake in preheated oven for 9-10 minutes, until the cookies are just lightly browned on the edges.
4. Remove from the oven and leave to cool.