Preheat the oven to 375°F. Grease an 8-by-8-inch baking pan or line with parchment paper.

Put 3/4 cup of the oats into a food processor (or blender) and pulse until the oats form a flour. Pour into a medium mixing bowl and set aside.

Add the dates and apricots to the food processor with the lemon juice and water. Allow the mixture to sit and soften for 30 minutes. Blend until the mixture is smooth.

Add the remaining 2 cups oats and the lemon zest to the bowl with the oat flour. Pour in the date-apricot mixture. Stir until well combined, and then pour the mixture into the prepared baking pan.

Bake until the edges become golden brown and the mixture feels firm to the touch, 35 to 40 minutes.

Remove the baking pan to a cooling rack. When cool, remove from the pan onto a cutting board and cut into squares. Set the bars on the cooling rack to firm up a bit more, about 10 minutes.

Store in an airtight container or resealable plastic bag for up to 1 week. To warm, reheat in a 375°F oven for 6 to 8 minutes.