Preheat the oven to 300°F (150°C).

Place the sun-dried tomatoes in a bowl and cover with the boiling water. Set aside to soak for 5 to 10 minutes.

In a large bowl, stir together the remaining ingredients.

With a slotted spoon, scoop the softened sun-dried tomatoes out of the soaking water and transfer to a mini food processor, reserving the soaking water. Process the tomatoes until minced. (Alternatively, you can chop the tomatoes by hand—just be sure to chop them very fine so the crackers are easy to slice.) Scoop the tomatoes into the bowl with the seed mixture.

Add the tomato soaking water to the bowl with the seed mixture. Stir for about a minute, until the water has been mostly absorbed by the seed mixture and is no longer pooling on the bottom of the bowl.

Transfer half the seed mixture to each baking sheet (or if using one extra-large baking sheet, spoon all of it onto the sheet). With your hands, spread the mixture starting in the center and pushing outward, until you form a large. misshapen rectangle, no more than 1/4-inch (5mm) thick. (The mixture will be very wet, but this is normal. Be sure that the dough is uniform in thickness and the corners aren't too thick.)

Bake for 30 minutes. Remove the baking sheet(s) and using a pizza slicer, carefully slice the dough into large crackers. Carefully flip each cracker using a spatula or your hands. Don’t worry if a couple break here and there! If for some reason the crackers are sticking to the parchment paper, just leave them as is and remove them after the second bake.

Return the baking sheet(s) to the oven and bake for 23 to 25 minutes more, until the crackers are golden. Watch closely during the last 5 to 10 minutes of baking to ensure they don’t burn. Remove from the oven and let cool on the baking sheet(s) for 5 minutes. Transfer the crackers to a couple of cooling racks and let cool completely. Store the cooled crackers in a paper bag on the counter for up to 1 week. You can also store them in an airtight container in the fridge for up to 1 week or in a freezer-safe zip-top bag in the freezer for 3 to 4 weeks. If the crackers soften while storing (this can happen in humid environments), toast in the oven at 300°F (150°C) for 5 to 7 minutes, then let cool completely. This is usually enough to return their former crispness.