Preheat your oven to 180 celsius (350 fahrenheit) and place your oven rack on the middle shelf. Line 2 large baking trays with baking paper.
Grab a large mixing bowl and add the flour, oats, sesame seeds and sugar. Mix well.
In another bowl or jug and combine the tahini, golden syrup, olive oil and all but the last tablespoon of the water. Use a whisk and stir until smooth. In a small bowl add the remaining tablespoon of water and add the bicarb (baking) soda and mix well. Add this and the tahini mixture to the dry mix. Mix everything until all the dry ingredients are absorbed.
Use a teaspoon to scoop the mixture into small balls (roughly 15mm/ ½ inch diameter). Flatten with the back of your hand and place on the baking tray, making sure the cookies are evenly spaced. Bake for 10 to 12 minutes until lightly golden. Lave the cookies on the tray for 5 minutes (the cookies will be very soft still) before placing on a wire rack to cool completely.
If you don't have golden syrup you can use brown rice syrup or honey.