By definition, to be a braggot at least half the fermentables have to come from honey.
By whose definition? Braggot is a very loose term for a beverage made with malt and honey.
I wouldn't worry too much about sanitizing the honey I've been making no-heat, no-sulfite meads for years without a single infected batch. I mix my honey with room temp water, stir until well mixed, pitch the yeast and let it go. Many flavors and aromas in honey come from volatile compounds that evaporate when honey is heated.
You could blend finished beer with finished mead.
You could add honey to your favorite beer wort to bump up the gravity.
You could add some malt for flavor, to your favorite mead recipe.
Deciding when, where, and how is completely up to you.
From my experince, I have found that malt can contribute assertive flavors to braggot (a good thing). I like to use a more flavorful honey to allow the honey flavors to find balance with the malt. Here on Hawaii Island I use eucalyptus honey and Christmas berry honey for making braggots. I save my mild-flavor honeys for show meads.
I don't like the flavor of hops in my braggots, so I don't use them, but that's my preference. You may find hops to be good in braggot.
Have fun with it. Add a can of malt extract, a half gallon of honey,to enough water to make 5 gallons, mix it up good, throw an ale yeast in there and see how it turns out.