2 large carrots, trimmed, scraped, and cut into ¼-inch slices
1 medium head red cabbage, cored and thinly sliced
1 medium head cauliflower, cored and florets broken into bite-size pieces
1 red bell pepper, stemmed, seeded, and cut into 1-inch pieces
¼ tsp. crushed red pepper flakes, plus more to taste
5 large garlic cloves, peeled and left whole
3 c. water
1½ c. distilled white vinegar
1½ tbsp. coarse kosher salt
⅓ c. granulated sugar
2 coriander seeds (optional)
2 allspice berries (optional)
Stir together all cut-up vegetables and garlic cloves in a large tempered glass bowl or divide the mixture evenly between large glass mason jars, making sure to include all of the vegetables; reserve.
In a large pot, combine water, vinegar, salt, sugar and coriander seeds and allspice berries, if using. Stir to dissolve salt and sugar and bring mixture to a boil. Remove pot from heat and carefully ladle hot mixture over reserved vegetables. Cover bowl or put lids onto mason jars. Let mixture stand at room temperature for at least two days; strain and serve.
Unused pickled vegetables may be kept covered in the refrigerator for up to one week.