By: J.Patterson

Gluten-free, nutty, and utterly addictive—these peanut butter cookies blend oat and buckwheat flour for a rich texture, balanced with just the right touch of Maldon salt and miso. A childhood favorite, all grown up.

Who Doesn't Love a Good Peanut Butter Cookie?

Like most things we do here, this recipe comes from childhood. I think I was seven or eight when my mom first made peanut butter cookies for Christmas. I remember sneaking them from the cookie tin and hiding under a desk in the office to devour them, completely hooked on that salty kick. Looking back, I suspect the salt was a mistake—because these weren’t just lightly salted; they had the kind of savory edge you’d expect from a cheddar scone or a cracker on a cheeseboard. The kind that melts in your mouth. And honestly? I never forgot it, because I’d never had a cookie quite like that then.

This version started with that unforgettable Christmas in the ’90s and has evolved over the years as we’ve leaned into fermented ingredients (hello, miso) and embraced gluten-free baking for the many GF folks we host at the castle. It’s got that perfect balance—deep, nutty, a little salty, and just indulgent enough.

Here’s how we make them.

Ingredients

Dry:

85g oat flour
85g buckwheat flour 
½ teaspoon baking soda
Pinch of salt (or miso for extra depth)

If you don't want gluten-free fabulous nutty cookies, you can of course swap the oat and / or buckwheat flour for all-purpose at a 1:1 ratio. That said, we find the gluten-free options flavorsome and readily available or easy to mill at home in an oysterizer.

Wet:

115g coconut oil (solid but soft at room temp)
120-150g demerara sugar (adjust for sweetness preference)
1 large egg (room temp)
185g creamy peanut butter
10 ml (1 Tbsp) Amaretto (optional, but recommended)

 

Instructions

  • Preheat & prep – Heat your oven to 175°C (347°F). Line a baking sheet with parchment paper.
  • Mix the dry – In a bowl, whisk together the oat flour, buckwheat flour, and baking soda.
  • Cream the wet – In a separate bowl, beat the coconut oil and sugar until well combined. Mix in the egg, peanut butter, miso, and amaretto.
  • Combine – Gradually fold the dry ingredients into the wet mixture until a thick dough forms.
  • Scoop & salt – Roll the dough into small balls and place on the baking sheet. Use a fork to press down slightly, then sprinkle with Maldon salt (optional)
  • Bake – Bake for 10-12 minutes, until golden but still soft in the center.
  • Cool & enjoy – Let them cool for a few minutes on the baking sheet before transferring to a wire rack.

Why This Recipe Works

Gluten-free & full of flavor – A blend of oat and buckwheat flour keeps it nutty and deeply satisfying.

Sweet & salty perfection – Eelevated with Maldon salt and miso for a crave-worthy balance.

Easily customizable – Skip the amaretto, choose crunchy or smooth peanut butter—make it your own.

Kick It Up a Notch (Totally optional, but worth it...)

Want to take these cookies to "I spent a summer in a pastry atelier" levels? A swirl of cashew cream and a walnut 'pendant' stuck on adds an extra layer of decadence and ornamentation (recipe below).

The cashew cream, in particular, elevates both the look and taste—effortlessly luxe with almost no extra effort.

Optional Topping: Cashew Cream & Walnut (Pendant)

(Smooth, lightly sweet, and perfect with the salty cookies.)

Ingredients:

100g raw cashews (soaked for 2-4 hours, then drained)
2 Tbsp maple syrup or honey
½ tsp vanilla extract
Pinch of salt
2-4 Tbsp water (adjust for consistency)

Instructions:

  • Blend until smooth, adding water gradually to reach desired texture.
  • Taste and adjust sweetness if needed.
  • Store in an airtight container in the fridge for up to a week.
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