In the bowl of your electric mixer (with the dough hook attached) add the sugar to milk, stir to dissolve and add the yeast. Stir gently, then let sit for 10 minutes. Melt the butter in separate bowl, add the beaten eggs to the melted butter, stirring constantly to make sure the butter is not too hot for the eggs. Add the egg/butter mixture to the yeast mixture. With the mixer on medium-low speed, allow the dough hook to stir this mixture for a couple of minutes, making sure it's thoroughly combined. With the mixer still going, add the salt and flour in 1/2 cup increments until all the flour is gone. Stop the mixer, scrape the bowl, then turn the mixer on the same speed for five minutes. After five minutes, stop the mixer and scrape the bottom of the bowl. Transfer the dough to a lightly oiled bowl and toss the dough to coat, then cover the bowl with plastic wrap and place straight in the fridge. Refrigerate dough for at least 8 hours, or overnight.

While the dough is refrigerating, make the pastry cream (it needs 4 hours to chill). In a small bowl, stir together flour, sugar and salt. In a large bowl, whisk together egg yolks. Slowly add the flour mixture to the eggs, whisking until smooth and pasty. Heat a saucepan over medium heat and add milk, allowing it to heat until bubbles form around the edges, but not boil. Remove the milk and slowly add it to the egg/flour mixture, whisking constantly until combined. Once smooth and mixed, add the entire mixture back to the saucepan, heating over medium heat and stirring constantly. Cook until it thickens and comes to a boil, about 2-3 minutes. Immediately remove from heat and strain through a fine mesh sieve, then whisk in the vanilla, lime juice, tequila and strawberry jam. Place in a bowl and cover with plastic wrap, pressing it until it touches the surface of the cream. Chill for at least 4 hours.

Remove bowl from fridge and turn out dough onto a lightly floured surface. Roll out to 1/4 to 1/3-inch thickness. Using a 3-inch cutter, cut as many rounds as you can, then roll out remaining dough and cut as much as you can. Place the doughnuts on a floured baking sheet. Cover with large towel and place in a warm place in your kitchen. Allow doughnuts to rise for one hour (mine were good to go after 50 minutes). Doughuts should be puffy and airy.

While the doughnuts rise make the strawberry margarita frosting. Slice strawberries and puree with the strawberry jam, milk, tequila, vanilla and lime juice. In a medium bowl, using an electric hand mixer, beat the butter until light and smooth. Beat in 2 1/2 cups powdered sugar. Add the strawberry mixture and beat until smooth. Add more milk (or tequila) if a thinner frosting is desired. To make the lime glaze combine the powdered sugar, lime juice and tequila in a small bowl. Whisk to combine. The glaze will be thick, if it seems runny add some more powdered sugar. If it is just too thick to stir add some milk. Place the glaze in a sandwich size ziplock bag and snip the corner of the bag.

Heat a few inches of oil over medium-high heat in a large saucepan. Once the oil reaches 350 degrees F, add the doughnuts 2-3 at a time and fry until golden brown, about 2-3 minutes per side. Make sure you are using a thermometer and do not allow your oil to get too hot! The doughnuts need about 4-5 full minutes in the oil so the insides cook, and if it's too hot the dough will burn (trust me, I have burned my fair share of doughnuts). After frying, transfer each doughnut to a paper towel to let the excess oil drain.

While the doughnuts cool, beat the cold heavy cream in your electric stand mixer or with a handheld mixer until stiff peaks form. Fold in the strawberry margarita pastry cream. Take your time gently folding the the pastry cream, making sure there are no white streaks left. Using a pastry bag or ziplock bag, poke a hole inside the side of the doughnut and fill it with a bit of the pastry cream.

Dip the doughnuts in the strawberry frosting of frost with a butter knife or spoon. Using the the lime glaze make a swirl on top of the strawberry margarita frosting. Sprinkle the whole doughnut with salt. If desired top with a sliced strawberry.