Whole and ground fennel seeds originate from common fennel, Foeniculum vulgare “Purpureum.” Unlike sweet fennel, or Foeniculum vulgare “azoricum,” which is sliced for salads or baked in the oven, common fennel is bulbless. Sometimes called sweet cumin because its flavor is reminiscent of cumin, common fennel has seeds with a distinct licorice taste and scent. Use them with anything from soup to nuts.
Whole, Crushed and Toasted Seeds
Recipes normally called for whole or crushed fennel seeds; ground fennel is used less often. Crush the seeds with a mortar and pestle, in a coffee grinder or, with a bit more difficulty, with a rolling pin or two spoons. Be careful with the grinder, or your efforts will result in ground fennel as opposed to crushed fennel. As with other spices, toasting the seeds in a dry frying pan for a minute or two releases the seed’s fragment oils and flavors. Once you can smell the seeds, you’ll know they are finished toasting.
Crushed, whole or ground seeds go well in spice cookies, quick breads and savory muffins or scones. Add crushed seeds to yeast breads as well, especially those with other flavorful ingredients such as walnuts or dried figs. Or sprinkle fennel seeds on top of breads or crackers before baking. A seed-topped flatbread from the University of California Berkeley Wellness Letter uses a mixture of sesame, pumpkin, sunflower and poppy seeds, but you could add fennel seeds to the mix as well. The recipe calls for a sprinkle of Parmesan over the seeds to help hold them in place.
Meats and Fish
Fennel seeds, whole or crushed, add a signature taste to homemade sausage made from beef, chicken or tofu crumbles. Use toasted and crushed seeds in a marinade for fish, chicken, pork or lamb. Or add the seeds to a dry rub or a topping for roasted or barbecued meat and fish. Ina Garten, chef of Food Network’s "Barefoot Contessa," uses 2 tsp. of fennel seeds, 6 cloves of garlic, 1/3 cup of fresh rosemary and 2 tbsp. of lemon zest for a paste she blends in a food processor and rubs on a pork loin roast before baking.
Salads, Sauces and Soups
Dietitians at the MayoClinc.com website liven up the flavors of potato soup with 2 tsp. of toasted fennel seeds and 2 tsp. of lemon juice. Mark Bittman, author of “How to Cook Everything Vegetarian,” suggests fennel seeds in yogurt sauces for meats and fish and in any salad dressing. You’ll taste fennel seeds in many Asian dishes, particularly those from India and Sri Lanka, according to Charmaine Solomon, author of “The Complete Asian Cookbook”; in these cuisines, the seeds are toasted and used both crushed and whole.