Have a look at the example in this link :
http://docs.angularjs.org/api/ngSanitize.$sanitize
Basically, angular has a directive to insert html into pages. In your case you can insert the html using the ng-bind-html directive like so :
If you already have done all this :
// My magic HTML string function.
function htmlString (str) {
return "<h1>" + str + "</h1>";
}
function Ctrl ($scope) {
var str = "HELLO!";
$scope.htmlString = htmlString(str);
}
Ctrl.$inject = ["$scope"];
Then in your html within the scope of that controller, you could
<div ng-bind-html="htmlString"></div>