Apple-oat crumble bars

Method

1. Heat the oven to 175°C. Line a 20 cm square tin with a parchment sling and lightly grease the exposed sides.
2. Combine the oats, oat flour, walnuts, 4 g cinnamon, and salt. Whisk the melted butter, almond butter, maple syrup, and vanilla separately until smooth, then stir into the oat mixture until evenly moistened.
3. Reserve 220 g of the mixture for the topping. Press the remainder very firmly and evenly into the lined tin. Bake for 10 minutes.
4. While the base bakes, cut the apples into 8 mm dice. Toss with the lemon juice, remaining 2 g cinnamon, and cornstarch.
5. Spread the apples over the hot base and press gently into an even layer. Pinch the reserved oat mixture into small clusters and scatter it across the fruit.
6. Bake for 32 to 38 minutes more, until the apple juices bubble at the edges and the crumble is golden. Cover loosely with foil if the top colors early.
7. Cool completely in the tin for at least 2 hours. For the cleanest bars, chill for 30 minutes before lifting out and slicing into 12.

Added Sugar Check

The maple syrup contributes about 48 g added sugar to the pan, or about 4 g per bar. Use unsweetened almond butter; sweetened nut butter would increase the total.

For a no-added-sugar version, replace the maple syrup with 60 g cup-for-cup granular monk-fruit/erythritol baking blend and add 30 ml milk. Keep the butter and almond butter unchanged. Press the base especially firmly; the bars will brown less and may be slightly more delicate.

Notes

• Gluten-free only when both the rolled oats and oat flour are specifically labeled gluten-free and every other packaged ingredient is verified. Ordinary oats are at high risk of gluten cross-contact during growing and processing.
• Some people with celiac disease do not tolerate oats even when labeled gluten-free. Follow individual medical guidance, and use clean bowls, tin, parchment, utensils, and work surfaces free from wheat flour.
• A tart, firm apple such as Braeburn, Granny Smith, or Boskoop gives the best contrast and keeps its shape.
• Refrigerate covered for up to 5 days. Freeze separated by parchment for up to 2 months and thaw overnight in the refrigerator.

Sources Consulted

• King Arthur Baking, “Apple Pie Bars”
• King Arthur Baking, “Chewy Granola Bars”
• Celiac Disease Foundation, “Gluten-Free Oats: What’s the Deal?”
• Celiac Disease Foundation, “Sources of Gluten”