Jam Diagonal Cookies: A Buttery Heirloom from Mom's Recipe Book

This is part of series of three holiday treats we made this year (2025). Growing up my mom make many different kinds of cookies. She would spend several days in the kitchen, usually while we were at school, baking away week before the holidays. We usually got a quick whiff of the sweet baked treats when we got home; but all evidence was usually cleaned up by our arrival. And for good reason. A fresh batch of baked cookies wouldn't last a few minutes let alone a few weeks!

I'd like to think things have change now that I'm an 'adult'. But the fact is now my wife has to hide them from me. Which can be tough since I tend to do most of the baking. These Jam Diagonals are Vung's favorite and she always loved them when we visited grandma for the holidays. Although she doesn't bake much, this is one of those occasions she's willing to break out the apron and fire up the oven.

Few treats capture the essence of family baking quite like Jam Diagonal Cookies—those buttery, jam-filled bars that evoke cozy kitchens and holiday gatherings. This recipe hails straight from my mom's cherished cookbook. We've baked multiple batches for our video series, each with slight variations, but the core remains: simple ingredients, no-fuss prep, and a result that's irresistibly comforting. Whether you're using homemade currant jam for a tart twist or classic strawberry from the jar, these cookies deliver a melt-in-your-mouth texture that's perfect for cookie swaps, afternoon snacks, or sharing stories around the table.

What sets this apart?

The dough's high butter content makes it crumbly and rich, almost like a shortbread, while the diagonal cuts add a fun, elegant touch. My wife and I love teaming up in the kitchen for these, laughing over measurements and debating jam choices—it's real-life baking at its best, full of nostalgia and zero pretense.

Ready to roll up your sleeves?

Here's the easy recipe to get you started:

Ingredients:

• 1/2 cup unsalted butter, softened

• 1/4 cup granulated sugar

• 1 large egg

• 1 teaspoon vanilla extract

• 1 1/4 cups all-purpose flour

• 1/8 teaspoon salt

• Your favorite jam (e.g., strawberry, grape, or homemade currant) for filling

Instructions:

1. Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper for easy cleanup.

2. In a large bowl, cream the softened butter and sugar until smooth. Beat in the egg and vanilla extract.

3. Gradually add the flour and salt, stirring until a soft, crumbly dough forms—don't worry if it's dry; that's the butter working its magic.

4. Divide the dough into 3 equal portions (about 122g each for precision, if you're feeling meticulous). Roll each into a 9-inch log or rope, using a light dusting of flour if needed to prevent sticking.

5. Place the logs about 3 inches apart on the baking sheet. Use your finger to press a 1/2-inch deep trough down the center of each log.

6. Fill the depressions with jam—go generous for extra flavor, but watch for runny varieties that might spread.

7. Bake for 12-15 minutes, until the edges turn lightly golden brown.

8. Let cool on the sheet for at least 30 minutes, then slice diagonally into bars for that signature look.

Pro Tip: Opt for homemade jam if possible—it holds up better in the oven and offers a less sugary, more authentic taste. If the dough crumbles, just press it back together; imperfections add to the homemade charm!

Catch the full baking adventure in our video below, where we share the process, jam experiments, and a few family anecdotes. It's like stepping into our kitchen for a heartfelt session.

Check out the details in the video below!

https://www.youtube.com/watch?v=5RRv7NtXyVc