Every year I make several batches of ANZAC biscuits (they’re so easy!), and every year I completely forget which recipe I used last time — except that I always add miso paste to the mix, for a saltier, richer, chewier biscuit. 
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This year, my hunt for the “right” (ie. chewy — fight me) reference recipe naturally began with the Australian Women’s Weekly “Beautiful Biscuits” cookbook, published in 1982 and showing its age with directions like “cook in a slow oven”, but otherwise an excellent starting point (not that I ever should have doubted).
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So here’s my perfect chewy salty ANZAC biscuit recipe, adapted directly from the prototype. Someone at the CWA would probably have kittens at the addition of miso paste, but trust me, it’s a winner.

Gather:
1 cup rolled oats
1 + 1/3 cup plain flour
1/2 cup white/caster sugar
1/2 cup (packed) dark brown sugar
3/4 cup shedded coconut

125 g butter
2 tbsp* golden syrup**
2 tbsp white miso paste
1/2 tsp baking soda
1 tbsp boiling water

Then:

1. Preheat the oven to 320ºF/160ºC.

2. In a large mixing bowl, combine the oats, flour, sugars and coconut, mixing with a fork until everything is evenly distributed.

3. In a small saucepan, melt the butter, golden syrup and miso together. (The miso might take some coaxing to dissolve.)

4. In a small bowl, mix the baking soda and boiling water together, then add to the saucepan and stir gently until it froths up.

5. Add the wet ingredients to the dry, and mix with a wooden spoon until fully combined.

6. Take heaped tablespoons of dough, roll into balls, and place on a parchment-lined baking sheet (you’ll need two trays, or work in batches). Remember to leave at least 2 inches of clearance, to allow for spreading.

7. Bake until evenly golden brown — the time will depend on your oven, but around 15 minutes (go by how they look, rather than the clock). The biscuits will spread on their own, and will remain chewy even when fully cooked, so there’s no need to underbake.

9. Remove from the oven and allow to cool on the trays, on a cooling rack. (They’ll fall apart if you try to move them too soon.)

10. These are best eaten on the same day, when the surface is a bit crispy and the inside gently chewy, but they (famously) keep very well in an airtight container.

Notes:
*These are 20ml tablespoons; if your tablespoons are 15mls, you can just overload them a bit.
**Golden syrup can be difficult to find outside Australia/the UK, but is available from major online retailers and at bigger supermarkets (in the ‘British foods’ section). If you can’t get your hands on some, try a 50/50 mix of molasses and light corn syrup.