1. Soften safely (30 minutes planned): Cut cream cheese into small pieces and let soften about 30 minutes. Take sour cream and eggs out shortly before mixing. Softening may take longer in a cool room; include any extra time. Keep dairy/eggs out of refrigeration less than 2 hours total, or 1 hour above 90°F. Wash hands, equipment, and surfaces after handling raw eggs. Do not taste raw filling.

2. Prepare crust (15 minutes): Heat oven to 350°F (177°C), center rack. Lightly grease a light-colored 9-inch square metal pan, at least 2 inches deep. Line with a parchment sling extending about 1 inch above two opposite sides. Keep this lining in place throughout. Mix crumbs, crust sugar, salt, and melted butter until evenly damp. Press into an even bottom-only layer using moderate pressure with a flat-bottom measuring cup.

3. Prebake (10 minutes): Bake crust 10 minutes, until fragrant and set. Remove to a rack and reduce oven to 325°F (163°C). Let crust cool about 10 minutes while mixing the filling in the next step; this cooling overlaps that step and is not an extra wait.

4. Mix filling (15 minutes planned, including crust cooling): With a hand mixer or stand mixer paddle on low-to-medium speed, mix softened cream cheese and sugar until smooth, scraping bowl. Add sour cream and vanilla; mix just until combined. Add eggs one at a time on low, stopping as soon as each is incorporated. Gently fold with silicone spatula to check for unmixed pockets. Spread over briefly cooled crust, leaving at least 1/2 inch space below rim. No water bath required.

5. Bake filling (45 minutes planned): Bake at 325°F for about 40–50 minutes. Edges should look set and the center should tremble gently, not slosh. Verify center reaches at least 160°F with an instant-read thermometer, without touching crust/pan. If needed, continue checking every few minutes. Do not wait for the entire surface to become rigid or deeply brown. Baking time depends on oven and pan; 45 minutes is an estimate.

6. Cool and chill (45 minutes + at least 6 hours): Cool in the metal pan on a rack for about 45 minutes, then refrigerate promptly, even if still slightly warm. Do not leave it out to cool completely. Loosely tent until cold, then cover without touching the surface. Refrigerate at least 6 hours, or overnight, until fully cold and firm. Refrigerate sooner in a hot room; never exceed 2 hours after baking, or 1 hour above 90°F.

7. Prepare topping (10 minutes): After the cheesecake has chilled, measure topping ingredients and set out cream and butter briefly so they are not refrigerator-cold. Preheat oven to 300°F (149°C). Set aside a baking sheet and a heavy, light-colored stainless saucepan with ample room for foaming. Use a long heat-safe spoon/spatula and oven mitts; caramel can cause severe burns. Keep children/pets away.

8. Toast pecans (10 minutes): Spread nuts on baking sheet and toast 8–10 minutes, stirring once, until fragrant. Remove, let cool while making caramel, then roughly chop about half. Do not let nuts burn.

9. Make caramel (15 minutes planned): Put the 1 cup sugar in the dry saucepan over medium heat. Stir constantly with a heat-safe utensil as it clumps, melts, and turns amber, about 6–10 minutes. Once fully melted and amber, lower heat. Carefully stir in softened butter; it will foam. Slowly add cream while stirring, standing back from steam and splashes. Return to medium heat and boil about 1 minute, then remove. Stir in fine salt and toasted pecans. Do not taste while hot. If sugar smells burnt or turns black, do not use that batch.

10. Cool topping (30 minutes planned): Transfer to a suitable heat-safe bowl if desired. Let cool about 30 minutes, stirring occasionally, until no longer hot but still spreadable. Allow extra cooling if needed; never pour hot caramel onto cheesecake. If too thick to spread, warm gently, stir, and cool again. Keep cream-containing topping refrigerated promptly if not using.

11. Top (5 minutes), chill (30 minutes), slice (5 minutes): Spread cooled pecan caramel over cold cheesecake. Add optional flaky salt sparingly. Refrigerate about 30 minutes to firm topping. Lift chilled slab using parchment onto a board; use three cuts in each direction for a 4-by-4 grid, 16 bars. Warm a sharp knife in hot water, wipe dry, and clean between cuts. Serve chilled and return leftovers promptly to refrigerator.