Help please, how many cookies?

Hi All
New here and asking for advice, hope that's ok?!

I made some canna butter following a recipe I found online which suggested 1lb of butter to 1oz of weed. I had 10g of bud and so used 300g. All done and finished and STILL had nearly 300g of butter so not even sure if it's gonna work.

Anyway in order to use this big lump, I've made butter biscuits. Least they're yummy if they don't work lol and I've made 20 from the above. So 0.5g per cookie (if it all worked ok of course)

So the question is how many should I eat to catch a buzz? lol
Any help appreciated thx :D