A citrus delight! The sweetness of freshly squeezed oranges mixed with the tart sour note of limes create a balanced combination of flavours layered on top of a rich shortbread (or your favourite blondie bar). Create any citrus combination, truly! Lemon-Lime, Grapefruit-Orange... you get the point. Perfect treat with an afternoon tea!
Preheat oven to 350°F or 176°C. Use a rectangular 9 x 13 inch baking pan with a 3 inch height (or casserole dish will work too), line with parchment paper on the sides and bottom.Pro Tip: Use softened butter to brush the sides and bottom of the pan prior to placing parchment paper to keep the paper in place and fold down the extra overhang on the outside of the pan. (for easier lifting)
Add 1 stick of butter to a small saucepan on medium heat and stir continuously until all of the butter is melted. Keep stirring until it starts to bubble and brown bits appear on the bottom of the pan (about 3 - 4 minutes). Remove from heat and stir another 30 seconds. Set aside to cool.
Melt 1 stick of butter in the microwave ( 30 to 45 seconds). In a large bowl, combine melted butter, browned butter, sugar, salt, flour, lime and orange zest. Mix thoroughly with a spatula until dough appears to be dense and thick.
Press shortbread dough firm and evenly into prepared pan. Place on middle oven rack and bake for 20 minutes or until edges are very lightly browned. (key is to under cook because a second bake will be done with filling. Remove from oven (do not turn oven off) and set aside.
In a large bowl, whisk (by hand) together orange, lime juice, salt and eggs until well incorporated (2 minutes). Add sugar, flour and whisk until thoroughly combined. Pour over warm shortbread crust and bake uncovered for another 25 minutes or until the center no longer jiggles.
Let cool to room temperature. Cover with plastic wrap by gently flattening against filling surface to remove any air bubbles and place in the refrigerator to chill for 4h or overnight to allow filling to set.
When ready to serve, lift the shortbread out of the pan. Add confectioner's sugar to a small sieve and dust over entire shortbread. Cut into squares and serve with hot beverage of choice. Enjoy!
1. Store leftover shortbread in an airtight container for up to 1 week.2. To freeze, individually wrap each bar with plastic wrap and place into a resealable freezer bag for up to 3 months.3. To thaw, let bars defrost in the refrigerator for a couple hours. Sprinkle more confectioner's sugar before serving.How far in advance can I prepare the bars? Note that the bars need at least 3 to 4 hours of chill time in order for the filling to set. Plan to make these in the morning or the night before.Room temperature Dairy ingredients This seems like an unnecessary step but makes a big difference when utilizing dairy at room temperature vs. cold from the fridge. The reason for this is when mixing ingredients at room temperature the dough will mix/blend better together more easily for a smoother batter or dough without clumping. Plan ahead and leave ingredients on your counter overnight or at least 30 minutes to 1 hour ahead. Browning Butter, is this necessary? No it's not. I browned 1 stick butter to deepen the crust flavour (aka. hint of nut without actual nuts). Feel free to brown both sticks of butter if you prefer and add an even deeper level of nutty flavour to your crustEggs Crack eggs into a mug or measuring cup. I like doing this so it's easier to add 1 egg at a time to the filling (also easier to remove excess shell). Pro tip: crack egg against countertop instead of side of bowl. It reduces the chance of small egg shells dropping into your cup when you crack it.