Blackberry Hazelnut Crumble Bars

I am writing this on the very first day of autumn. Copenhagen has welcomed this season with classically crisp air and blindingly bright sun. People are stretched out along the banks of the harbour in the afternoon light, soaking in what will be the last blows of summer’s fight. Ugh. Can you feel it?

Last week my family and I were out at our garden. On the cycle back home we stopped by the blackberry bramble that has overtaken a major section of the vacant land nearby. It towers over me, and extends along the bike path for half a block or more, an impenetrable wall of thorns and fruit. Happily there were a few berries left, just enough to pick for a dessert and a handful to snack on with my boys. Languishing in the last morsels of hot sun we felt the seasons shifting ever-so-slightly and celebrated with the ripest and blackest of berries, like summer captured in edible jewels.

But I got the berries home and suddenly I felt a lot of pressure. Kind of like when you impulse-buy those crazy-looking mushrooms at the farmer’s market and worry that whatever you’re going to be making isn’t “special enough” so you let them sit in your fridge too long until they go bad. Forehead slap. That was not going to happen to my berries. No way. Here was my thought process:
Sarah B, relax.
You like blackberries.
You like crumble.
You make too many crumbles.
You don’t make too many bars.
Crumble bars.
What’s a crumble bar?
Stop asking questions. Let’s do this.

I proceeded in the best way I knew how, by browsing the internet for ideas. It turns out crumble bars do exist, but I couldn’t find any versions that were all that virtuous. Subbing this for that while keeping things as simple as possible, I came up with an edition that is made with whole foods, totally vegan, and easily made gluten-free. The crust is light and flaky, the filling is rich and bursting with juicy flavours and the crumble topping is crunchy and satisfying. Although I use hazelnuts in mine, you could substitute those with almonds – just leave a few of them really big because biting into a large toasted nut is delicious, especially combined with the oozy and sweet fruit center. Heavenly.
Next year I am definitely going to try these bars with black currants in the early summer months, and maybe raspberries later on.

Freezing and Cooking: How do they affect nutrients?
Pssst. I have a secret. Sometimes in the off-season, I do something totally crazy. I buy frozen berries.

What is a nutritionist such as myself doing purchasing and even recommending frozen foods to people? For one, I live in Denmark where the availability of fresh food is pretty sad in the winter, obviously. And second I’m a person that does things like everyone else, such as relying on conveniences when need be. I’m okay with that.

But what kind of affect does freezing have on foods, say blackberries for instance? You’d be surprised, and likely thrilled to learn, that freezing does not completely spoil the vitamins and minerals in food. In fact, you’re looking at a mere 10-15% nutrient loss across the board. Vitamin C is the one vitamin that is most likely to dissipate, as once the fruit or veggie has been plucked from its source, vitamin C levels start to decline almost immediately. Luckily, vitamin C is the single more common and easily obtained vitamin in nature, and you can make up for that loss somewhere else in your day.

And what about cooking? This is a little more complicated, as it varies according to the specific nutrient in question and the type of cooking method. Fat soluble vitamins (D, E, K) are not destroyed by heat alone, and vitamin A is relatively stable. The B-vitamins are also heat stable, except for panthotenic acid (B5). Folate breaks down at very high temperatures. Vitamin C is the nutrient that takes the biggest hit by far, as it is one of the most delicate vitamins in nature. It is not only destroyed by heat, but also exposure to air and light. It is also water-soluble, meaning that steaming something containing vitamin C will be surely destroy it.

As a general rule, minerals are very heat stable, especially when using cooking methods that do not employ water, like roasting or baking – there is almost no loss whatsoever.

If you are steaming, boiling, braising, or blanching foods, both vitamins and minerals will leach out into the water. To preserve these precious nutrients, save the broth to drink, or freeze it for later use in a soup or stew. I use it to puree my baby’s food. He’ll never know his millet porridge was cooked with broccoli water!

Since this blog is read the world over, there will of course be a few of you out there who can’t get themselves to a blackberry bramble, simply because it isn’t the right season. No worries. Find a grocer with organic frozen blackberries and go to town. You should not wait to make these. Seriously.

Print recipe

Blackberry Hazelnut Crumble Bars
Makes 12-16 bars

Crust:
2 ½ cups / 250g rolled oats, divided (gluten-free if desired)
¼ cup / 60ml applesauce
¼ cup / 60ml pure maple syrup
1 Tbsp. coconut oil
1 tsp. vanilla extract
½ cup / 50g whole rolled oats
¾ tsp. fine grain sea salt
1 tsp. baking powder

Filling:
4 cups / 400g blackberries (fresh or frozen)
½ Tbsp. ground cinnamon
¼ tsp. ground nutmeg
¼ tsp. fine grain sea salt
zest of 1 organic lemon
½ Tbsp. arrowroot powder (or organic, non-GMO cornstarch)
1 Tbsp. maple syrup

Crumble Topping:
1 cup / 100g rolled oats
2 Tbsp. pure maple syrup
2 Tbsp. coconut oil (or ghee)
2/3 cup / 75g hazelnuts
½ tsp. ground cinnamon
¼ tsp. sea salt
2 Tbsp. flour, gluten-free if desired (I used brown rice flour)

Directions:
1. Preheat oven to 350°F/175°C.
2. In a food processor blend 2 cups / 200g oats on high until you have a rough flour. Add applesauce, maple syrup, coconut oil, and vanilla. Pulse until moist.
3. In a separate bowl combine the remaining ½ cup / 50g rolled oats, salt, and baking powder. Add food processor contents and fold to combine, using your hands to mix – the dough will be quite firm.
4. Place the dough into a lightly greased 8”x8” brownie pan and press firmly, especially around the edges – it helps to wet your hands so that the dough doesn’t stick.
5. Without cleaning the food processor, add the all the ingredients for the crumble topping, and pulse a few times to mix. You can chop the ingredients as finely as you like, but I left mine very chunky – it’s your call.
6. To make the filling, place all ingredients in a medium bowl and toss to combine. Put them on top of the uncooked crust and spread evenly – the berries should just cover the crust in one layer.
7. Sprinkle the crumble topping over the blackberry layer. Place in the oven for 30-35 minutes, until slightly golden on top. Let cool completely before cutting into bars. Store in the fridge for up to five days.