Step 1

Preheat oven to 300°. Toast pecans on a large rimmed baking sheet, tossing once halfway through, until fragrant and slightly darker, 18–25 minutes. Let cool. Transfer to a food processor and pulse, scraping down as needed, until the texture of peanut butter. Add miso and pulse just to combine.

Step 2

Meanwhile, bring grapes, cinnamon, salt, and 1 cup water to a boil in a medium saucepan. Reduce heat to medium-low and simmer, stirring occasionally, until grapes have burst and liquid is jammy, 25–35 minutes. Let cool, discard cinnamon stick, then mash with a potato masher.

Step 3

Assemble sandwiches with bread, miso-pecan butter, and grape jam.

Step 4

Do Ahead: Pecan butter and grape jam can be made 1 week ahead. Cover and chill.