Trilbies (Old-Fashioned Oatmeal Date Filled Sandwich Cookies)

Prep:15

Cook:10

Total:8 25

Yield: sandwich cookies

Equipment

Ingredients

Cookie Batter:

1 ½ c. salted butter softened
1 c. granulated sugar
½ c. brown sugar packed
1 ½ c. unbleached all-purpose flour (RECOMMEND WEIGHING)
4 ½ c. quick cooking oats
¾ c. boiling water
1 ½ tsp baking soda
½ tsp baking powder

Date Filling:

8 oz. whole dates pitted & chopped
⅓ c. cold water
½ c. brown sugar packed
1 tsp lemon juice

US Customary - Metric

Instructions

Make the Dough: Cream butter, granulated sugar, and brown sugar until light and fluffy. Mix in flour and oats. Dissolve baking soda and baking powder in the boiling water, stir in vanilla, then add to the dough. Mix well—the dough will be very soft and runny (this is normal).
1 ½ c. salted butter, 1 c. granulated sugar, ½ c. brown sugar, 1 ½ c. unbleached all-purpose flour (RECOMMEND WEIGHING), 4 ½ c. quick cooking oats, ¾ c. boiling water, 1 ½ tsp baking soda, ½ tsp baking powder
Shaping Options (choose one): Option A – Freeze & Slice (recommended for crisp edges and perfect round cookies): Divide dough into 3 equal portions. Place each portion on a large sheet of cling wrap/plastic wrap. Roll into a uniform log about 2 inches in diameter. For perfectly round logs, slide the wrapped log into a clean paper towel cardboard tube. Twist the ends of the cling wrap to seal. Tape shut and freeze at least 8 hours (or up to 1 month). To bake: Unwrap frozen logs, then slice a generous ⅛-inch thick. Place slices on ungreased baking sheets. Option B – Refrigerate & Scoop (easier for beginners): Cover and refrigerate dough at least 4 hours (or overnight). To bake: Scoop 1-Tbsp portions onto ungreased baking sheets. Flatten each to about ⅛-inch thick with the bottom of a glass dipped in flour.
Make the Date Filling (while dough chills/freezes): In a saucepan, combine chopped dates, brown sugar, ⅓ cup water, and lemon juice. Bring to a boil over medium heat, stirring constantly. Reduce heat and simmer 4–6 minutes until thick and jam-like. If dates are dry and mixture isn’t softening, add more water 1 Tbsp at a time. Cool completely before using.
8 oz. whole dates, ⅓ c. cold water, ½ c. brown sugar, 1 tsp lemon juice
Bake: Bake 9–11 minutes until edges are pale golden (centers may look slightly underdone—they crisp as they cool). Pro shaping tip: Immediately after removing from the oven, while cookies are still hot and soft, gently nudge the edges of each cookie with a round cookie cutter (slightly larger than the cookie) to create perfect circles. Work quickly before they cool and set. Transfer to cooling racks.
Assemble: Once completely cool, spread a scant 1–2 teaspoons of cooled date filling on the flat side of one cookie. Top with a second cookie, flat side down, and press gently.
Storage: Store in an airtight container with parchment between layers: up to 5 days at room temperature, 10 days in the fridge, or 2–3 months in the freezer. They taste incredible straight from the freezer!

Notes

Cling wrap + cardboard tube upgrade: Highly recommended over wax paper—cling wrap releases cleanly from frozen dough, and the taped cardboard tube keeps logs perfectly round for uniform slices.
Yield variation: Expect 60–80+ sandwich cookies depending on slice/scoop thickness and any trimming. Thinner slices = more cookies.
Date tip: Fresher dates cook down easily; drier ones may need the extra water for a smooth filling.
Short Term Storage: Store assembled cookies in an airtight container for up to 5 days or for 7 days in the fridge. Using parchment paper between the layers is a good idea so the cookies do not stick together
Long Term Storage: Freeze the cookies using parchment paper or plastic wrap between layers in a freezer-safe container for 2 to 3 months.
Best Flavor: Their flavor only gets better after a day or two. They taste BEST straight from the freezer.

Nutrition

Servings: sandwich cookies

Calories: 100kcal