Big Batch Crumble Bars

This isn't really a new recipe but it's so much more convenient to have my doubling already done! Especially since I've been lowering the amount of sugar I use. Original EATS recipe at http://eatseats.blogspot.com/2015/05/berry-crumble-bars.html

I always double this recipe now (the quantities you see below) because I then cut it into squares and freeze, ready to take out for breakfasts. One 9x13 pan makes enough for at least a month or two.

An even easier way to portion out the crumble bars is to use muffin tins! I take about 2/3 of the crust mixture and use a small portion scoop to fill as many muffin cups as it can (usually about 24). I have the kids flatten the crust portions to fill the bottom of the muffin cup. Then we use the same portion scoop to put a scoop of filling in each cup and then divvy up the remaining 1/3 of the crust mixture on the tops. Doing it this way makes them less crumbly and makes the whole experience of getting even portions so much simpler. If you want bigger ones, just use a bigger scoop and make fewer.

INGREDIENTS

Filling
2 12 oz bags berries of any type, fresh or frozen--I don't bother to thaw first (24 oz total)
1/3 c sugar (I used coconut sugar but any type would do)
1/4 c ground flax (or you could use 6 TBSP flour)
2 tsp ground cinnamon
Splash of water if the berries are frozen

Crumble crust
(these are rough guidelines--mix and match to the same number of grams with the nuts and grains you've got)

100 g rolled oats
200 g rye flakes (or any combination of any flakes)
120 g almonds (Gordon specifies sliced but I've used whole with no issues; I just pulsed them a few times before adding the other ingredients)
60 g pepitas, pecans or sesame seeds
240 g whole wheat flour (soft or hard wheat or spelt though the bars might be a bit crumblier with spelt)
125 g sugar (Gordon calls for light brown sugar but I've also used just plain sugar with no problems)
1 tsp ground cinnamon
2 tsp kosher salt
1 1/2 tsp baking powder
16 TBSP (225 g, 2 sticks, 1 cup) unsalted butter, cold and cut into small cubes
2 large eggs, beaten
4-8 TBSP ice water

DIRECTIONS

1. Grease a 9x13 in rectangular pan or prepare 18-24 muffin cups by greasing. I use non-stick cooking spray in both cases. Preheat the oven to 350F 
2. Place all of the filling ingredients in a small saucepan and heat over medium, stirring a few times, until the mixture is bubbly. If you're using frozen berries, add a splash of water to help them not stick to the pan and stir more frequently at the beginning. Set aside
3. If using whole nuts, process them briefly in the food processor until they're chopped medium fine
4. Add the remaining ingredients up to the butter and pulse together until blended and chopped fine
5. Add the butter and pulse until the mixture looks like small peas
6. Add the beaten eggs and pulse until combined
7. Add the water and pulse, starting with 2 TBSP. Expect the mixture still to look crumbly but it should be clumping together
8. Press about 2/3 of the crumble crust as evenly as you can into the bottom of the prepared pan
9. Pour over the berry filling
10. Distribute the rest of the crumble mixture over the berries somewhat evenly
11. Bake about 30 minutes, or until the topping is browned