1. Rinse cranberries and discard any that look bad or squishy

2. In a saucepan, combine cranberries, water, and 6 tbsp sugar; bring to a boil over medium-high, then simmer 10–15 minutes (stir often) until berries break down; cool 30 minutes

3. Preheat oven to 325°F (163°C); line a 9-inch square pan with parchment (overhang helps lift) and grease well

4. Make crust: mix melted butter, 1/4 cup sugar, vanilla, and salt; stir in 1 cup + 1 tbsp flour until a thick dough forms; press evenly into pan

5. Bake crust 16–18 minutes until lightly golden; remove, poke all over with a fork; cool 20 minutes (turn oven off)

6. Make lemon layer: whisk 3 tbsp flour with 1 cup sugar; whisk in eggs, then lemon juice until smooth

7. Spread cooled cranberry mixture over crust to the edges; refrigerate 45 minutes to set

8. Preheat oven to 350°F (177°C); gently pour lemon layer over cranberry layer

9. Bake 43–45 minutes until center is set and no longer jiggles; cool 1 hour at room temp, then chill 1–2 hours

10. Dust with powdered sugar; lift out by parchment and cut into 16 squares (wipe knife between cuts for clean edges)