Peanut Butter Choc-Chip Cookies

"How do you like your cookies? With a bit of crunch? Or at the other end of the spectrum, with only a crisp edge to hold together a soft, gooey middle? Personally, I like a not-too-soft, not-too-hard kind of cookie. Just right – a Goldilocks cookie? Ingredients: 2 tbsp ground flax seeds (see optional substitutions below, too) 100g/1 cup rolled oats 130g/1 cup self-raising flour 140g/⅔ cup caster sugar ⅛ tsp fine salt 160g/⅔ cup creamy smooth peanut butter* 90ml/6 tbsp plant-based milk e.g. soy 30g/scant ¼ cup dark dairy-free chocolate chips"