Go fresh over frozen or canned whenever possible.
This is the simplest step to make broccoli or kale taste better. There's a huge difference in taste between fresh and frozen as freezing cruciferous vegetables brings out their bitterness. Freshly purchased broccoli or kale will taste good but they'll taste even better if you grow your own. It's pretty much impossible to match the taste of any freshly picked vegetable.
Add some garlic and olive oil.
Garlic and olive oil is a classic pairing with broccoli or kale. Simply get some olive oil, pour a little on a saucepan, mince the garlic, and sauté before eating. Then sprinkle on some sea salt once it's done for some more flavorful kale or broccoli.
If you don't have have any garlic available, garlic powder or garlic salt is a nice, quick substitute. You could also use Kernel Seasons Garlic Parmesan seasoning.
Add some ranch.
What doesn't ranch go with? It definitely works with broccoli and kale. Simply prepare your broccoli like you normally do and then add the ranch before eating.
Try some butter and freshly, ground black pepper.
This is another classic pairing that works great on a variety of foods. Just make sure to use a black pepper grinder instead of a black pepper shaker. There's a huge taste difference with just a little bit more effort.