Prepare the fruit:

1. Heat the oven to 375°F and lightly butter a 9 × 13-inch baking dish or similar 3-quart baking dish.
2. Core the apples and pears and cut them into roughly 3/4-inch pieces. I’d leave the apple skins on if they’re tender; peel the pears only if their skins seem particularly tough.
3. Quarter the figs.
4. Toss the apples and pears with the lemon juice, brown sugar, flour, cinnamon, ginger, nutmeg, salt, and vanilla.
5. Gently fold in about 3 of the quartered figs. Transfer everything to the baking dish.
6. Scatter the remaining 2 quartered figs over the surface, tucking them slightly down among the fruit. This gives you a better chance of getting recognizable bits of fig rather than having all of them melt into the filling.

Make the crumble:

1. Combine the oats, flour, brown sugar, cinnamon, and salt.
2. Add the cold butter and work it in with your fingers until you have a mixture of fine crumbs and larger buttery clumps. Mix in the nuts, if using.
3. Scatter the crumble evenly over the fruit. Don't pack it down.

Bake:

1. Bake for 40–50 minutes, until the crumble is golden brown and the fruit juices are bubbling noticeably around the sides and in a few spots through the topping.
2. If the top is browning faster than the fruit is cooking, loosely cover it with foil for the final 10–15 minutes.
3. Let it rest for at least 20 minutes before serving. That gives the pear and fig juices time to thicken instead of running everywhere when you scoop it.