1Make the jam filling: Add the blueberries, 2 tablespoons lemon juice, and 2 tablespoons honey to a medium saucepan over medium heat. Bring to a boil, crushing berries with the back of a spoon. Reduce the heat to low and simmer for about 8-10 minutes until thick and jammy. Remove from heat, stir in chia seeds and 1 teaspoon lemon zest. Set aside to cool.
2Make the base layer: In a medium bowl, mix together quick oats, almond butter, 1/3 cup honey, 1 tablespoon lemon juice, 1 teaspoon lemon zest, vanilla extract, and salt until well combined.
3Line an 8x8-inch pan with parchment paper. Press about 1 3/4 cups of the oat mixture evenly into the bottom of the pan.
4Spread the cooled jam filling evenly over the base layer.
5Crumble the remaining oat mixture over the top.
6Refrigerate for at least 2 hours until set.
7Make the lemon glaze: In a small bowl, whisk together powdered sugar and 1 teaspoon lemon juice. Drizzle over the top of the bars and sprinkle with lemon zest if desired.