Like Par said, make coming inside 1000% better than being outside. Inside is the place for attention, food, water, playtime, and best of all, treats. If Gracie won't come inside for regular dog treats, microwave a hot dog and chop it up in small pieces. Bring her inside and spend 5 or so minutes on training - sit, shake, etc. Use the hot dogs to entice her in and give as a reward when she does come inside. Once inside and training, give her some less fattening dog treats.

Since she already has issues with coming inside, never punish her or make it a bad experience no matter how mad you get. (I know it's hard, but you can do it!)

No matter the means you use to get her inside (enticing with hot dogs or holding her collar), praise, praise, praise her for coming in.

I have one that's pretty dense too, but food MOTIVATES her like nothing else.

I also would do the NILIF program. Nothing in the universe has helped me more than that has.