I went to the farmers' market yesterday in search of tomatoes but came home with beautiful, fat, ripe blackberries instead. Time for crumble.
I did a lot of experimenting over several summers to finally settle on this recipe. It uses equal parts flour, oats, butter and sugar. But not just any sugar. You could probably use regular brown sugar and it would be good. Probably better than good. But I love the old-fashioned flavor of the oats with the sandy texture of demerara sugar.
Demerara is a raw cane sugar. It has larger crystals making it crunchier. I love the sandy, crumbley texture it gives baked goods. I also like that it's less processed and still contains the natural minerals found in cane sugar. It's more expensive than regular brown sugar, but can be found in most baking sections of the grocery store. I just use it for special occasions like this crumble where it really adds star power.
You could use this crumble topping with just about any fruit that strikes your fancy. When making this with peaches, I sprinkle in a little cinnamon with the fruit. Out of desperation in the winter when you need a little sunshine, you can even make it with frozen fruit. But be sure to let the fruit thaw and drain completely to get rid of the excess juices or it'll just be sludge.
You can also make this topping up to a day ahead and keep it in the fridge. Then just spinkle it over your berries when you're ready to bake, and it goes together really quickly.
I think blackberries are my favorite crumble filling. They have a sharper, tarter flavor that contrasts really well with the sweetness of the crumble topping. The two things seem to really enhance each other.
But whatever filling you use, taste your fruit first. I always put a little cornstarch with the fruit to thicken the juices that bake out, but you might also add a little sprinkle of sugar, if the fruit isn't as sweet as you'd like. These berries were pretty tart, so I used about a tablespoon of sugar with the berries.
The other thing to consider when making this crumble is what size pan to use. Depends on whether you like thick crumble with deep fruit or thinner crumble with shallower fruit. I usually bake it in a pretty wide casserole pan, but this time decided to use my deep Emile Henry pie pan because it's blue color looked so pretty with the berries. I had 4 pints of berries so I doubled my crumble topping recipe. In addition to filling the deep pie pan in the photo, it also filled a small casserole dish.
The recipe below will fill a regular pie pan.
3/4 cup flour
3/4 cup old-fashioned rolled oats (not instant and not steel cut)
3/4 cup demerara sugar
3/4 cup cold, unsalted butter, cut into chunks
1 teaspoon vanilla
2 pints blackberries
1 tablespoon sugar (optional, to taste)
1 tablespoon corn starch
In food processor, combine flour, oats, sugar and salt. Pulse a few times to combine. Add chunks of butter and process in pulses until crumble starts to come together like a dough ball. Pour crumble into a large bowl and make sure all of the butter is mixed into the dough. If there are any butter wads left, you can mix them in with your fingers or a dough cutter or two knives. (If you want to bake your crumble later, cover and refrigerate.)
Preheat oven to 375 degrees.
Place your berries in the bottom of your pie pan. Spinkle with sugar, if using, and cornstarch. Stir to combine. With your fingers, sprinkle crumble topping over top of berries evenly.
Place pie pan on a cookie sheet, just in case there's any blackberry juice spill over, and bake for 45-55 minutes. Check it after about 30 minutes and cover with foil if it begins to brown too much on top.
If you can stand it, let cool for at least 30 minutes. It's also fine to bake and let cool on the counter for several hours before serving. You can serve it fancy with vanilla ice cream or whipped cream, but it's really good just straight up. We've found in our research that it's particularly good for breakfast the next morning too.
Can easily be doubled or tripled depending on how much fruit you have. But note: my standard food processor maxes out at a double load of crumble topping. So you might need to make that in batches.
Blackberry crumble. The flavor of summer.