Preheat the oven to 350ºF.
Lightly oil an 8x8-inch or 9x9-inch baking pan and line it with foil or parchment paper, leaving flaps so you can lift everything out at the end.
Sift the flour, measure it, and spoon it into a medium bowl. Then add in all the other batter ingredients. You don’t need to add them in any particular order. Stir everything until it is smooth and uniform—this should take less than a minute.
Spread the batter in the baking pan, put in the oven and bake for 18 – 22 minutes depending on your oven. It will be done with a tester poked in the center comes out clean.
Cool on a rack for about 10 minutes. Lift out of the pan, using the flaps; set on a serving plate, carefully peeling off the paper. Make the glaze, adding only enough lemon juice to make this spreadable. While the blondies are still warm, spread the glaze on top.
That’s it! You’re done. Cut into squares and serve.