ASPEN APRES-SKI: Casa Tua’s Michele Grendene wasn’t the only one celebrating a new Aspen outpost over the holidays — Dennis Basso raised a Champagne flute or two for his newly expanded retail digs in the Little Nell Hotel. Domenico De Sole, Rena Sindi and Jamie Tisch were among the 500 well-wishers who joined the designer for a runway show and Champagne and caviar cocktail party at The St. Regis hotel. During the auction, art collector and philanthropist John Phelan dropped $120,000 for a Russian sable coat for his wife Amy. The auction’s $350,000 tally contributed to the evening’s $600,000 grand total for the Aspen Art Museum. As New Year’s neared, Basso helped keep the cash register ringing in his 2,000-square-foot boutique — triple the size of his previous one. Apparently, a few Aspenites warmed up from the slopes in his $95,000 Russian sable vests with crocodile trim and $200,000 sable coats.