I can’t believe I haven’t shared this recipe yet, but apparently I haven’t!  They are a staple option in our house!

The recipe is adapted from the Flour cookbook -  Flour is the name of a fabulous Boston bakery and pretty much everything in this cookbook is heavenly. You know the recipe is good from the state of the cookbook page…anything covered in a mess is a safe bet I’ve made it more than a few times and splattered the page in the process!

These very popular bars are great to keep around  - they work nicely any time of year and they are a perfect treat with a cup of coffee or tea to have on hand when guests drop by.

I like to keep some in the freezer just in case.  This also keeps me from just eating them all every time I walk by…

Today I’m making a batch to add to the Christmas gift baskets I’m assembling for a few friends and family members. 

There *may* be some leftovers for the household (and the chef, of course) - at the very least we get the trimmed edges!

This recipe calls for cake flour - which I forgot I didn’t have until the butter and sugar was already happily in the mixer.  Faster (and cheaper) than running out to the store, is making your own.  All that cake flour is, really, is flour that is finer and with less gluten thus producing a slightly softer, crumblier baked good.   These are shortbread bars so slightly crumbly is desirable.

To make your own cake flour requires only 2 ingredients: all purpose flour and corn starch.  I always have both of those on hand!  Simply substitute 2 tablespoons of flour for 2 tablespoons of corn starch for each cup of flour.  

Measure a cup of flour. Remove 2 tablespoons and put them back in the canister. Add 2 tablespoons of cornstarch.  Sift the mixture at least twice (some recommend 5 times, but this feels a little like overkill for this recipe).

The recipe in the cookbook is quite detailed.  I’ve streamlined it a bit.  I like to make these fairly thin using a 13” x 18” half sheet size pan which results in ~3 dozen delicate sized bars perfect to serve at teatime (BTW all day is teatime in my house!).  The original recipe uses a 9” x 12” pan and says it makes 9 bars…making them VERY substantial and about a zillion calories a piece! 

I also like using raspberry jam with seeds - it just feels more like real fruit to me, but you can choose whatever you like and even substitute in a different flavor of jam!  These would be equally fantastic with apricot jam, for example…

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These are my favorite tools that make this recipe easy:

A standing mixer (honestly, if you bake much, this makes SO many recipes easier!)

Half sheet precut parchment paper

An offset spatula for spreading the jam

A microplane ribbon grater for grating the dough for the crumble layer

A pizza wheel for cutting the squares (not at all necessary, but SO easy and fast!)

Raspberry Crumble Bars

Adapted from the Flour cookbook by Joanne Chang

Makes ~ 3 dozen thin squares

Ingredients

• 3 sticks of unsalted butter, softened

• 1/2 cup granulated sugar

• 3 Tbsp confectioners sugar

• 2 egg yolks 

• 1 tsp vanilla extract

• 1 1/4 cups all purpose flour

• 1 1/2 cups cake flour

• 3/4 tsp baking powder

• 3/4 tsp salt

• 1 1/2 cups (12 oz jar) raspberry jam (I like the Hero brand, but homemade is never wrong either!) 

• Confectioners sugar for dusting - I use the King Arthur non-melting dusting sugar so it doesn’t disappear on you (it even holds up if you freeze them!)

Directions

• In the bowl of an electric mixer, beat butter with the 1/2 cup of sugar and 3 Tbsps confectioners sugar on medium high speed until light and fluffy (5+ minutes), scraping down sides.

• Add egg yolks and vanilla and mix, scraping down sides with a spatula to make sure it is thoroughly mixed.

• Sift together flours, baking powder and salt in a medium bowl.

• Add flour mixture to butter mixture gradually with mixer set on low speed.

• Increase speed and mix 15 seconds more or until flour is thoroughly incorporated.

• Turn mixture out onto plastic wrap and gather into a ball.

• Separate 1/4 of the dough mixture and shape into a log. Wrap in plastic wrap and chill in freezer.

• Flatten the remaining dough into a rough rectangle shape about 1” thick and wrap with plastic wrap and refrigerate to chill for 30 minutes.

• Preheat oven to 350º F.

• Remove chilled dough from refrigerator. Unwrap and dust both sides lightly with flour - I like to use a flour wand for this.

• Place dough on parchment sheet and roll out into a rectangle the size of the baking sheet/parchment. If dough is sticking to the rolling pin, add a top layer of parchment to assist with rolling.

• Place parchment topped with dough on baking sheet - trim any edges, peel off top layer of parchment if you used one.

• Bake for 20 minutes until just beginning to color.

• Remove from oven (leave oven on).

• Microwave jam in jar (without the lid) for ~1 minute to soften. Pour jam onto baked shortbread and spread in a thin even layer using an offset spatula.

• Remove dough log from freezer and grate shavings evenly over top of jam using a coarse hole size grater. The dough softens quickly, so work as fast as possible and grate directly onto the jam.

• Return pan to oven and bake 25 more minutes.

• Remove from oven and cool.

• Dust top with confectioners sugar (I like the non-melting variety for this) and cut into squares trimming off rough edges (these are a tasty treat for the cook and anyone nearby :-))

These keep well in a container at room temperature for several days, or in the freezer for several months.

ENJOY!