I make some version of this almost every September, when plums are cheap and nobody wants to peel anything. That's really the appeal of this plum oatmeal crisp: you cut fruit, you rub together a topping, you bake. It's no wonder the desserts that stick around are almost always the ones with the fewest steps, like this one.
I always had some version of fruit crisp (made in individual ramekins) when I ran my own café kitchen, back in the day, and plums were always in demand, so it's about time I shared it with you.
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Sweet and tart dessert
The idea is simple: dump the plum pieces in the dish, mix together a few ingredients for the crumble, sprinkle it over the fruit and pop the baking dish in the oven. You'll have a bubbling, juicy dessert in less than an hour.
Plums are underused for this. Everyone reaches for apples out of habit, but plums bring their own uniqueness: they break down into this loose, jammy, slightly winey syrup as they bake, very different from, say, an apple crumble. You want the fruit layer wet and a little unruly under a topping that's doing the opposite, staying craggy and crisp where the plums are soft.
What's the difference between crumbles and crisps? It has to do with whether you use rolled oats in the topping or not. A crisp recipe uses oats, and a crumble doesn't. The truth is that both are used interchangeably.
Make ahead: You can freeze the baked dessert in the dish, or just the crumble, and assemble them together an hour before eating. It'll be ready when you're done with dinner.
Dessert for a crowd: Crisps and crumbles in general, and this one in particular, are a no-brainer dessert to make for a barbecue, a picnic, a weekend lunch, especially during good weather months. It's easy to make several of them at a time, and it's rare that people don't like it.
Serving it: Though this crumble is great served warm with a scoop of vanilla ice cream or whipped cream, it's also amazing plain, warm or at room temperature.
Testing notes
Paula's baking tips that make a difference.
There is no need to peel the plums. The skins soften during baking and add color and flavor to the finished dessert.
My ideal plum is ripe but still reasonably firm. They should be juicy and flavorful without being so soft that they are difficult to cut. That said, this is also a great option for less-than-stellar plums, with little flavor.
Old-fashioned rolled oats are best for this recipe because they provide more texture. Quick oats can work, but the topping will have a finer, less substantial texture.
Don't skip tasting a raw plum before you commit to the full amount of sugar in the recipe. Plums vary wildly; some are almost too sweet to need any sugar at all, others are sharp enough to pucker.
How to get the crispest topping? By using melted butter and refrigerating the crumble before using it. The butter temperature matters more than people think. It needs to be melted, yes, but let it cool until it's just barely warm; if it's hot, you'll get a paste instead of clumps. Chilling it while you prep the plums helps it firm back up and adds that great, crisp texture to each bite.
Steps to make plum crumble with oats
For the topping, I recommend a pastry cutter or your hands (my favorite, always) and a large bowl, because it's a little messier. You can use the food processor, but be careful of processing the oats or overprocessing the whole mixture; you want large clumps.
Crumble topping
This clumpy oat crumble mixture is made with melted butter and refrigerated while making the filling. You can make it several days ahead and keep it in the fridge or frozen.
This is my go-to streusel topping option, as it bakes to a crisper, more golden brown with noticeable clumps, and is the one that's sure to be a hit with everyone.
Plum layer
I recommend fresh ones. Frozen pieces soften more during baking.
The filling ingredients are simply stirred in the baking dish for ease and convenience. But you can use a separate bowl for this step if it's easier for you.
Assemble the dessert
Break up large clumps if needed before sprinkling the topping over the prepared plums.
While you need to cover most of them, leave some gaps around the edges to allow the steam and juices to bubble up during baking.
Baking a plum crisp
The dessert is ready when the top is dry and golden brown, and the juices are bubbling.
Paula's tip
Let the dish cool down for 30 minutes or so before serving, to allow the juices to thicken a little and the topping to crisp up. If you serve it immediately, it will be soupy and not as crunchy.
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Plum Crisp Recipe (Oat Crumble Topping)
Ingredients
For the topping mixture:
- 1 cup all-purpose flour
- 1 cup old-fashioned rolled oats
- pinch of salt
- ¾ cup packed light brown sugar
- ¼ cup granulated sugar
- ½ cup unsalted butter, melted and cooled but still liquid
For the plums:
- 1 ½ pounds fresh plums
- ¼ cup granulated sugar, use less if you prefer a more tart dessert
- 1 tablespoon fresh lemon juice, depending on how tart the plums are
Instructions
- Preheat the oven to 350°F (180°C).
Make the oat crumble topping:
- In a large bowl, combine 1 cup all-purpose flour, 1 cup old-fashioned rolled oats, a pinch of salt, ¾ cup packed light brown sugar, and ¼ cup granulated sugar.
- Add ½ cup unsalted butter, melted and lukewarm (not hot!). Mix with a fork or spatula until combined. Refrigerate while you prepare the fruit.
Prepare the plum layer:
- Have a 9x13-inch oven-safe ceramic baking dish ready. You can butter it if you like.
- Cut 1 ½ pounds fresh plums into small pieces, discarding the pits, and spread them evenly in the baking dish. Sprinkle with ¼ cup granulated sugar and 1 tablespoon fresh lemon juice. Toss gently to combine. If your plums are very sweet, you can use 2 or 3 tablespoons of sugar.
- Cover the fruit with the chilled crumble, breaking up any large pieces as needed, but don't press it down. It will be unevenly distributed, and that's perfectly fine.
- Bake for about 40 minutes, until the topping is dry and golden and the plums are bubbling.
- Let cool on a wire rack until warm, about 30 minutes. Serve as is, with whipped cream, or with vanilla ice cream.
Tonya says
It looks yummy
Angie says
It was delicious, definitely making it more often