Feeling in the need for some biscuits (like you do on occasions), I searched the internet for some recipes that both looked and sounded good.
The first one I tried was from Tesco recipe page (oops, advertising!) You can find it here
I only had normal jumbo oats (not normal sized or GF), so used those. I also halved the cinnamon and added 1/2 oz less sugar as we don't like things over sweet. Finally, the baking time was extended to 15 minutes as that is how long our oven took to bake them.
As ours came out a different colour, we wondered how they got their biscuits to look so brown. I think maybe 190C next time, see if that makes a difference.
I know, I KNOW:) You are supposed to follow these recipes the first time but I couldn't help myself, I just like to twiddle.
They may taste different with different flour made up, this used a bought GF flour.
Anyway, they said it makes 35 but as they didn't give what size cutter to use, I used a 2" one and got what you see below (minus one we tested):
How long they will stay crisp we don't yet know. They say they will keep well in an airtight container for up to 2 weeks. We shall be offering them on our next walking day so doubt they will last 2 weeks.