Rinse figs and trim and discard stem and blossom ends. Coarsely chop figs. In a 3- to 4-quart pan over medium heat, stir figs, lemon juice, and granulated sugar until mixture is thick and reduced to about 2 cups, about 45 minutes. Chill uncovered until cool, about 1 1/2 hours, or cover and chill up to 2 days (see notes).
In a bowl, with an electric mixer on high speed, beat butter and brown sugar until smooth. In another bowl, mix flour, baking soda, salt, and oats. Stir or beat into butter mixture (dough will be crumbly).
Press half the dough evenly over the bottom of a buttered 9- by 13-inch baking pan. Spread fig mixture evenly over dough. Crumble remaining dough evenly over fig mixture; pat lightly.
Bake in a 400° oven until streusel is lightly browned, 20 to 25 minutes. Place pan on a rack to cool for about 10 minutes. While still warm, cut into 24 bars. Let cool completely in pan.
Yum! Scrumptious! I made these with figs from my yard, and they were delicious. The fig mixture took significantly longer than 45 minutes to cook down to 2 cups, but it was worth the extra time. It resulted in a thick jam-like consistency, almost like the filling in a fig newton. I didn't have an electric mixer, so I beat the butter and brown sugar by hand, which took a little effort but not too much. I used 1 cup all-purpose flour and 3/4 cup whole wheat flour instead of all all-purpose flour, which gave the bars a slightly nutty taste. I also added chopped pecans to the topping, which was a nice touch. I cooked the bars the full 25 minutes. I can't wait to make these again!
The first time I made this recipe, I took it out of the oven after 20 minutes. It needed the full 25. The second time I made it, I added a half cup of chopped pecans on top and baked it for the full 25 minutes. Sorry, but it was too good to share with anyone. Yum!