A plum assignment

"I have eaten
the plums
that were in
the icebox

and which
you were probably
saving
for breakfast

Forgive me
they were delicious
so sweet
and so cold"

- William Carlos Williams, "This is Just To Say"

I'm very grateful that nobody ate the plums that were on the counter, which I was saving to bake with. Especially grateful because I've never baked with plums before, and this recipe made a convert out of me. The jammy filling is delicious and sweet, and makes a perfect foil for the crisp base and topping. Now the only question is this: can I justify saving one of these for breakfast?

Plum Oatmeal Bars
(adapted from Canadian Living)

Makes about 20 bars

Ingredients:
3 1/2 cups chopped firm ripe red or black plums (about 5)
3/4 cup sugar (first amount)
1 Tbsp grated orange zest
1/3 cup orange juice
2 Tbsp cornstarch
2 cups quick-cooking (not instant) rolled oats
1 1/4 cups all-purpose flour
1/2 cup brown sugar
1/4 cup granulated sugar (second amount)
1/4 tsp salt
1 cup cold butter, cubed

Directions:

In saucepan, bring plums, 3/4 cup sugar, orange zest and orange juice to boil over medium-high heat. Reduce heat to medium and cook, stirring occasionally, until plums are tender and beginning to break down, about 12 minutes.

Whisk cornstarch with 2 Tbsp water; stir into plum mixture. Bring to boil, then cook, stirring, until thickened, about 1 minute. Scrape into bowl; place plastic wrap directly on surface. Refrigerate until chilled, about 1 hour. (Can make up to 24 hours in advance.)

While plum mixture is chilling, in large bowl whisk together oats, flour, brown sugar, 1/4 cup white sugar, and salt. Using pastry blender or two knives, cut in butter until mixture resembles coarse crumbs.

Firmly press half the oat mixture into bottom of parchment-paper lined 9" x 9" cake pan. Bake at 350 degrees until golden, about 20 minutes. Remove and let cool in pan for 5 minutes.

Spread plum mixture over crust. Gently press remaining oat mixture into small clumps and sprinkle over plum mixture. Bake at 350 degrees until topping is golden, 40-45 minutes. Let cool completely on board, then chill before cutting. Cut into 20 bars.